My thoughts on the timeline stuff:
-Imps should start with a full Grand Army of the Republic tech tree of ships they can build, and some of those items should start out with the first few upgrades already applied to represent the fact that those are ships that were just used in a major war and their being upgraded variants would make sense.
Nothing overpowering, just that for both sides clone war era or older ships should have the upgrade levels adjusted so the bottom few types get cut out.
-Try to tie EU stuff into what gets added as far as units and heroes, you could allow for building a limited number  of Republic Commando teams for example, also LAAT variants could be added, as well as LAATs being added to the standard build list.
-Neither faction should start out needing to research ships which were introduced in the previous era, if it's preexisting it should be buildable from the start.
 
 
 
Yeah, I'm thinking of removing the Acclamator I in favour of the Acclamator II, and possibly making the early ISD and VSD variants starting units only. The Empire already starts out with the Venator II instead of I. If I do this though, it would make more sense to start the campaign in 18 BBY. This will depend on if players who use my sub mod want to have buildable ISD's and VSD's with a V-wing complement or not. 
 
Other than that, this is already what I've aimed for somewhat. Rebels start with mark II Recusants, Z-95t's, Y-wing A4's. The Empire just doesn't use as many old units as the rebels do so it's not as visible on their side. The first few research costs for some of the old models are rather low though.
 
LAAT is already in the standard build list, it is buildable from the speeder factory. At some point I might add upgrade tiers to it. 
 
And neither side starts out having to research ships that were introduced in the previous era. There might still be some fine tuning here but it is what I am aiming for. But the ISD/VSD variants come to mind again, at the moment the V-wing complement variants are buildable from the start, but not the TIE complement variants. I've had to keep balance in mind here too, for example the Z95 AF4 should be available at the start of the campaign, but the AF4 is rather advanced in PR and would be considerably better than any other Rebel fighter. Hence why I picked the very common Z95t as the standard starting model, as it was still used in the GCW. I could of course just nerf the AF4, but that would make the Z95 upgrade tree very weird. 
 
Well, if you want to stick to SW Canon, The Victory-I, Acclamator-I, Venator-I are out to begin with. Now comes the interesting part the Victory-II should be buildable but only until the Imperial-I becomes available to build; same goes for the Venators. Canonically the production lines for those models were stopped in favor of the New Order's signature ship. The Acclamators, Dreadnaughts and Carracks should go as well but there's not yet any replacements that would be more canonical so...
 
It does limit somewhat the choice of ships you have at your disposal but it's the way it went in a GFFA. To be able to enjoy the Vics and Vens III-IV the best way would be to make upgrading those lines less pricey than unlocking the ISD; In that scenario the ISD has to be worth (power, usefulness, etc.) more than any upgraded Vics and Vens by a head if not more.
 
That's an idea I wanted to implement in my changes but my modding time has dropped to zero since I've begun working on various projects related to the mod. But that's alright seeing you guys go at it makes me recapture a little of the feeling you get when modding a game you really like. Go guys and thank you Chih for your efforts both on your creation and for brining some life to the community. :thumbsupsmiley:
 
Yeah, I want to stick to canon as much as possible. But I don't want to let the canon come in the way of fun. Which would be a bit of a problem if I modified the research tree to make all those units unbuildable after the Imperial I is available. The best way to go about here is in my opinion to let the player roleplay the change in Imperial doctrine. Another problem is that if I made the upgrade lines less pricey for the late model Vens and Vics, it would mean very strong ships for a cheap price unless I'd make them worse, which would again seem weird. 
 
So no, the Vics and Vens will remain buildable at all times. I might however test to make the change for the AI, so the Rebel player will have a more canonical experience. Similar changes might be done to the Rebel AI so the Imperial player gets a better experience. This is already implemented for the early ISD and VSD variants, which the AI cannot build at all (if you see any, it's units they have as starting units). 
 
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And thanks! Hopefully if people like my changes, they'll come back to check more often for my releases (I will try my best to release a new version once per month). And that in turn will make more people follow 1.3 more closely and notice any news about it! :)