My feedback based on the posted pics:

The index finger is at an angle..it should be straightened, and then most likely, the middle finger will probably need to be moved closer to it.

The thumb 3rd section looks too short to my eye.. and it's nail also looks very short to me.

The best hands I've seen are Girl 1's hands.. I always use them as a reference when I'm working on hands on other figures.
Maybe look at them for ideas on improvements?

If you've never rigged hands before, the easiest way to rig them is to start with the finger mesh  spread out, rig that, and then zero pose memorize them together.

Something I talked to someone else about at one point, was actually having 2 hand sections, with the fingers and thumbs coming off those two. That would at allow a more realistic hand pose option, however it defy's poser usual hand use, and poses.

Way too many people take way too many things way too seriously.