Better bosses to skull-rip, I mean it was an Emo Vamp Gang for one? Gimme a freaking break. I wish there were bonus trophies that could you take if you wanted to.
Maybe in one part where you're fighting Aliens, you happen to come across the Queen and a Predailen. That would make a worthy test of your hunting skills. For the Predalien, you would find a comrade in Rescue but as soon as you get him out, an Alien comes out. You can't get it for some reason, but find it again in the nest. Too bad they didn't have Facehugger, although it would be hard because it's third person and those little buggers can be hard without a Plasmacaster.