Yeah. I'd say Rippers and Bishop II. For a couple of reasons.
I don't think any of the Fiorina inmates or staff really warrant an action figure, except maybe Dillon.. ...and maybe Andrews. But as far as the pecking order goes, I'd say they're both lower on the list than Bishop and Ripley in terms of fan favorites. Then there's the issue of likenesses. Both Weaver and Henriksen have granted theirs in the past, so it's an easy bet that they will do so again. Why not? Signing a few contracts and getting your face immortalised on a toy fans will love sounds like a great way to generate a little extra income for not too much effort.
Then finally, that last scene of the movie. With Bishop II accompanied by his APE guys and Ripley about to plunge into the lead. That's a diorama wanting to happen.
-Windebieste.