Maybe articulated fingers. Better face sculpt, head that can actually look completely forward at a 90 degree angle, and I'm sure there's other stuff. Curious what the two extras could possibly be considering the creature pack.
Cracked bucket? lol
From the new arcade Dutch and Lin pictures you can see in the background the blue arcade alien which is based on the dog alien that it has the new ball jointed knees. Great for posing. Didn't see finger articulation, but would love that. Really doubt we'd get a new head sculpt. If we're lucky, we might get a few more degrees out of the neck. Though that's easily fixable. I used this trick on mine, worked like a charm.
The two accessories are an interesting question. If they go with anything from the creature pack, then that defeats the purpose of the creature pack, does it not? But what else could we get?