Peace through power, brothers!
Beware, my post will be quite long because i'd like to discuss all units, powers and building. which are useful, which are not and why and which are simply not used much for no real reason. Those that i don't mention are mandatory and its useless talking about them. (this is all based on my experience and the units i do or do not use)
Soviets
battle bunker. heavily overused. the battle bunker is extremely useful with all infantry and can easily be made universally good against all unit types. bunkers are low tier and easily one of the best defensive structures in the entire game.
sentry gun. underused. the defensive structure is cheap but its uses are limited. useful in a dire situation but overall not so useful. thats why its heavily situational and heavily underused.
tesla coil is a higher tier defence with longer range and damage but its again more situational than bunkers and is underused. i build them when there is no suitable terrain for bunkers or when i dont have the time to build a bunker and populate it with infantry. could be more cost effective anti armor than a bunker with better armor/heath but thats not by a lot to make it a superior choice.
sensor tower. i always build one in pve where most of my defences are and is typically less for its effects than just for the sake of it. in typical games you wouldnt want to waste money on it. its -10% health effect is too low, its only against a single enemy and defencewise it makes a lot less sense than having any one defensive structure in its place. also its heavy power useage is another heavy drawback. the additional plus for it is that you cant scout directly in its range but thats completely negated by manual scouting with dogs/units or using scout powers close by and scouting that area as a consequence. the usefulness of the building will be highest against few super high hp units at a place where you have a lot of defensive structures and that -10% will translate to more than having another defensive structure. needless to say this is extremely unlikely and right now the structure is rather useless. still building one (this building is not made to be build many times anyway) is actually a medium usage in pve and heavily underused everywhere else.
drakuv. underused. the unit is summoned with a support power which costs more than any other ground warfactory unit and has limited use. it fires very slowly and against vehicles its melee range. its effects are really fantastic and i summon 1-2 for the sake of it and hope they land the killing blow on units so i can get the tech for it but at their price they are not useful. against vehicles the unit sees even more limited use and is generally just a somewhat support/for fun unit at this time.
spy satelite overused early game and underused late game. as all map revealing skill, its very useful early on when you still havent revealed the entire map and also has some use later against allies. most of the time i sacrifice a dog to scout an enemy than wait for this power to come online.
naval mine underused. could be useful in naval battles where you tip a battle in your favour by using it but thats extremely rare occurance. the aoe damage of it is not that bad for its rather low price but because it cant kill units in one explosion, its more or less just waste of money.
repair drone. underused. the repair drone is a good on field repair vehicle but only one can be summoned and is very fragile. in most pvp battles it will be targeted, even if its in the back. its much more effective in numbers. for most defensive battles, battle cranes are superior.
battle crane medium usage. i always build them in positions where i may need to defend or just to repair costly units. the structure is very useful at repairing all ground and air units at a good rate and its cost is very good. the crane is high tier i build it after many higher priority structures that would provide me with a more imminent value
tank drop/terror drop. underused. i have a very positive opinion on reinforcement powers but the game is more focused on larger armies that these powers are just not very useful. i find terror drop better as even in small numbers they can do damage and costs less while tank drop is a waste of money. in a differently designed game they could be a lot more useful but in MO have very limited use.
overcharge. medium use. useful when you have enough tesla units and can have very high impact in battles. if i had huge tesla army all the time, i would see no reason why i wouldnt be spamming this power. right now its useful when you attack with tesla tanks but useless unless fighting or without tesla units.
smoke turret. underused. good for defensive lines vs AI but less useful in pvp as the enemy will evade it at all costs. overall its super effective defensive structure but its normally something you would build only just a few of them and will not need as many as you get.
motor ambush. underused. useless. the units cant deal any damage and is just a waste of money.
flame turret. underused. its a situational power that can have some uses when defending a valuable area outside of the base early on or preventing small infantry groups from moving unchecked but is easily destroyed and becomes very ineffective when heavy vehicles come into play.
smoke bombs. underused. another situational power which is actually very valuable. its most useful against big groups of units and if you hit your enemy's army right before attacking it will be super effective. most of the time the enemy wont concentrate his army in 1 place and this power will not be as useful in such situations.
emp mines. underused. useless
irradiation. underused. this power is good for its cost (no cost) and can deal some additional damage but most of the time i rely solely on the firepower of my units and its a rarety something would come close to my nuwas.
wallbuster. underused. only useful against a lot of costly defences so its uses are limited and it is not very cost effective otherwise.
gear change. underused. this economy power looks interesting but is only useful if you are completely broke and dont have any immediate means to get money. as long as you have a healthy economy, the power will only hurt your production.
emp. underused. i find myself rarely relying on this support power to fight vehicles. and i think this shouldnt be the case
iron guard. underused. this is a great defensive structure when you and your enemy have smaller armies but becomes less relevant later on. can be used to very great effectiveness if the enemy has limited attack routes.
iron curtain invulnerability. overused. very good support superweapon with smaller attack groups and can be very effective with many different unit types. not as useful when big armies clash
nuke. overused. i just love nukes. its my favourite superweapon just because its a nuke. i'd love it if you (mental meisters) change the animation to the nuke of the lionheart. i always try to build it and use it, even if its not worth the cost(money, time and power) at that point of time. the nuke is useful enough but its only mediumly strong. tempest is the strongest and lightning storm is the weakest. more to that later.
basic infantry. normal usage.
pyro and tesla trooper. overused, the backbone of the soviet infantry army, good against almost everything.
crazy ivan. underused. its cost and close range make it ineffective in most situations. its somewhat good at baiting the enemy but most of the time its a waste of money.
desolator and eradicator are very useful anti infantry/unit specialists but i rarely mass them. medium use.
chitzkoi and volkov. overused. very strong heroes with great universal use.
morales. underused. costly, easily killed and high priority unit that most of the time is a waste of money because its quickly targeted. its high range is not enough when he us that slow. defending him with a big army is not really worth the apm.
arsonist. underused. fantastic unit designwise but is too costly and easily detectable
saboteurs. overused. weak and easily killable units but i always try to get some new tech and most importantly warfactory veterancy. because if their high cost, not so easily spammable.
gyrocopter. overused. highly mobile units with good damage against masses of infantry. easily why i dont use more eradicators.
yunru. underused. can emp own units, useful as support but most of the time not cost effective. useless as eathshaker.
main battle tanks (all) deal no damage against infantry, base and air and they cant run over too many units. they fail as assault units and thats why most prefer to tech up and/or use different units. underused
anti air vehicles. medium use. these have a very specific use and very specific time for it. useful against most early game air but become outclassed later on when heavy anti air becomes available.
terror drones. overused? these are units which you would normally build only a few of and are for disruptive purposes. their effectiveness for cost is high but can be easily countered without proper micro.
borilo/armadilo. overused. these are heavy assault units which pretty much take the role of the main battle tanks. the infantry space inside make them that much more useful. build time is high so rushes are reasonably delayed.
bomb track/buggy. underused. these are expensive units that dont have enough damage for the risk they provide. only useful against structures and had to get to structures. much easier to use vs AI and can cause insane damage with iron curtain. bomb buggies are better because of their speed while bomb trucks may be rendered useless just because of units getting in their way or flat out destroying them.
tesla cruiser/catastrophy/nuwa cannon. overused. main t3 battle tanks that have some pros and cons but are overall very effective against most units.
scud launcher. overused. very good anti structure unit.
buratino. medium use. good against infantry but rather limited use vs buildings. can cause damage to your own units with fire.
centurion. underused. its limited quantity makes it too slow at dealing damage. nuwas are often the better assault unit. even at support (yunru, eradicators) the centurion is somewhat failing because of its slow speed. if you could built 2, then we would be talking.
dragonfly. underused. too much micro and monetary investment for large armies. could be very useful if small armies meet. very fragile.
fury drone. underused. too limited use and too high risk. its cheap enough to be useful but a standard unit yields similar effectiveness without that risk.
wolfhound/vulture. overused. both are fantastic defensive and supportive units but are normally used when there is no immediate thread. wolfhounds are anti armor and overall much more useful. at defensive play its universality is very valuable but heavy anti air renders it cost ineffective. vultures are the smaller brother that are not effective vs armor and their napalm is only situationally good. the high mobility makes them very good and useful but they cannot be used on their own vs anti air. ground units and/or building are needed as the backbone and protection vs anti air. their high tier can make them somewhat limited in the earlier stages of the game.
sentinel. overused. fantastic anti air and its heavy specialization can make the unit useless when no air units are used.
foxtrot. overused. very good anti unit jet bomber with fantastic aoe ability. i rarely skip them because they can provide insane value for their cost, even after the heavy nerfing.
kirov. underused. this is one very good unit as design and is something i love using in RA2 and YR but the anti air options in MO heavily counter it and make them a waste of money. if your economy is overwhelmingly stronger than the enemy, you can use them very effectively. also fantastic against foehn. you can quite safely get them to the enemy, shoot enemy defensive jets with wolfhounds and sacrifice some wolfhounds to the t1 anti air vehicles to take them out and deal heavy damage to the enemy. this strategy kills your opponent but if countered well will cost you a lot, maybe even the game.
dustdevil. underused. completely useless. for the confederation as the smoke bombing support power is much more effective and lot less costly. very situational use. against big strong armies with limited anti air they can prove useful but that is a rare sight.
the naval units are just basic and you cant do without them.
i will continue with the other factions at a later time.
i hope this whole post with spark some more discussions.
One Vision, One Purpose.