Ok, I won't write a treatise on this, but after playing all of the races/factions, I have come to the conclusion that this game needs some serious balancing love. Unfortunately, I don't think it will be easy, and many of the additional features are going to need some serious manipulation for everything to work.
Why do I say this? Well it's simple really. Back with Sins Vanilla, each race seemed to be better at a certain part of the game (i.e., TEC better early game, Advent better mid-game, Vasari better late-game, but could do well early game if the map was neutral rich). With each expansion, the times that races seemed to have advantages never really changed, but the difference has increased. With rebellion, the difference is now so pronounced (and even the timing has changed) that selecting a race that is good late-game is suicide.
What has made the difference worse is that I feel each race now has a very limited path to success. What I mean by that is that before you could use many different strategies for the same race. However, now each race/faction seems to have only one or two viable strategies (i.e., Vasari Loyalist must use strip to the core to have a fighting chance, but using it is totally OP), and those strategies all seem to be OP in their own way.
In times past, this game was a counter game (rock, paper, scissors). This lent itself to balanced fleets with frigates/cruisers/cap ships all rightly proportioned to get the right firepower (or if someone spammed a unit, you would spam the counter). Now, it seems most fleets are Titan/Cap ship heavy with support from carrier cruisers. Frigates seem to have gone extinct. Also, I think it goes without saying that corvettes are just completely and utterly broken at the moment (one of the reasons frigates are non-existent). They should not be good against everything.
Please discuss your thoughts on this. I know I didn't go into detail, but I am talking from a macro view of the game as a whole at the 100,000 foot level. There are plenty of examples, but I want to hear from people if this is their impression as well or if something else is going on. I want to see this game released being as close to reasonably balanced as possible, which will help ensure a healthy and active ICO.