can you do u.s. run without fucking up the indigenous territories?

At game start most of the indigenous territories are already fucked and you have a small Indian Territories vassal in Oklahoma. If you don't decide to settle what little indigenous land is left, The Hudson Bay Company and Mexico will probably do it.

can i basically destabilize the u.s. to go socialist or should i just try to build it up and RP a slightly less fucked historical progression?

Yes, though you may not get things to play out exactly as you'd like.