Hey Venom,
Good choice on the P1.
As for the second, what are the limits, ie, price point, what do you have already, any lines started already?
Not knowing what else you have, I'd go with Dutch. Perfect for the P1, and no other figures are NEEDED for that line unless you just love Billy or they make the full character lineup.
My most recent figure is the Rubber skin 600, and I love it even though I hate the idea of them in the movie, but if you don't have any TS figures, no need to start there.
If price is no object, then hit them up for the P2 Elder or a T-800 Endo.