Tried looking around, but couldn't find anything with solid info. Curious what the difference between Fighter 2 and Fighter 4 would be, other than the bonus feats and extra bab/hp.

Going for a Rogue7/Fighter4/WM7 build, or maybe Rogue9/Fighter2/WM7.

You gain access to weapon specialization at fighter 4 (+2 damage with a weapon) but that's not a big deal unless you're an archer, given the monty haul nature of the campaigns.

By going rogue 9/fighter 2 instead of rogue 7/fighter 4 is that you lose 1 BAB, plus 1 feat and some hp, in exchange for 1 sneak attack dice and some extra skill points you probably don't need (IIRC traps and locks are pretty easy in NWN 2).

Overall, it doesn't make that much difference, so feel free to choose what feels right to you.