@klord Other big things to be aware of, if you aren't already: @sinbad's got two killer plugins. SUDS for dialogue, and SUSS is his new Utility AI engine.
I'd call both must-haves at this point, for a particular kind of game. Dialogue just in general is a huge hole in Unreal, and this fills that well, and SUSS is shaping up to be what I wish Unreal had done instead of BTs.
I'm uh, one of those "Behavior Trees are garbage" people, so finding reasonable alternatives has been a big focus of mine. Joe Wintergreen has an FSM (essentially an HFSM) implementation I'm using now, and that's pretty alright, but I think Steve's SUSS is likely the one you really want for er. Most like, game'y games. FPSes and stuff.