This isn't going to be that helpful to you, but I think that the factions are so similar that they don't have long-term strategies. But I've only played three times. The different faction productions and faction actions may help to decide which cards to keep at set-up and in the first look out phase. After that you construct your VP engine on the fly. But that's just the sense I get after 3 plays, I'm ready to be educated.
I see the slight risk of the mutants and merchants to not get 2 wheels on turn one. But in the games so far contact tokens are very scarse resources and those two simply can generate 7 through the standard conversions, they seem just be much better for that reason. If I am to choose I'd NEVER take New York or Texas, how can those factions be balanced in general.
It is of course not imperial settlers with individual faction decks, but the difference of the factions is not that minor. And i feel it is kind of that for a mojority of the card draws all that generate more contact tokens through standard conversions are just better.