First of all, your problems are not "problems", i would call it dislikes at best.
1) Well, be glad they aren't all v3 rocket sizes then, then i'd call them HUGE
2) Really? last i checked fury missiles especially were stoppable and nova platform was cut as most of that thing doesn't make sense in practical future war.
3) As is intended, every n00b cries out initially until they L2P (Learn To Play!) and think outside standard RA2 gameplay so how about you try defending first.
4) Maybe you should try use them as mere means of buying you time to tech up and setup that economy than really try rely on them fighting your war for you...
5) In fast paced war, most of the time such troops die enroute to target unless its a bridge but then if you are playing maps with bridges, that only makes AI easier due to various flaws of game itself, play open area battles like heck freezes over for proper challenge.
It's like how Tanya was deemed worst hero always dying trying C4 buildings and stuff, if theres any c4 infantry in future, it will be limited.
Ok sure. Dislikes then. Except for the interception one. Its not that the AA guns can't intercept, its just that the tracking range is really really short. So by the time a missile is past the interception point, the turret is only just beginning to fire, meaning it doesnt take out the missile. That and Freedom's nuke chucker missiles are ridiculously fast.
The AI issue is this for me: Easy AI is pretty simple to beat. Normal AI will spam the shit out of me. In a normal game, the spam tactic wouldn't work because I'd have set up a fairly good turret line by then. Problem is that I can't intercept the artillery being chucked at me. I know that RA2 is NOT a turtler's game, which hurts me a little when it comes to actual attacks, but due to a WAVE of uninterceptable missiles coming at me, I usually don't last past the second wave.
I know that friendly AIs aren't supposed to win the game for you. I know that. They never have. However, they ARE supposed to be able to hold their own. SO when they do NOTHING in terms of troop buildup to stave off imminent death, theres something wrong. I build up my base and suddenly 5 "our ally is under attack" messages pop up in 10 sec and suddenly no more ally. I watch and its usually a wave of helicopter and ground troops against....5 or 6 basic turrets. I think the whole "AI meatshield" thing needs to be tweaked a little so they can at least put up a fight.