I am seriously debating pairing up the fingers, yes. While I like that the kit is true to the museum model, the fingers were never separated like that in the movie.
At the same time, it is my belief that the fingers were joined so that they wouldn't wiggle around because they were so long. If it was for practical reasons rather than esthetics, I'm not so into it.
However, it did create a lasting characteristic for xenomoprphs to have paired fingers until Alien Resurrection (which is canon in my book, though entertaining).
If I add the spurs, I might was well pair the fingers, right?
I won't add the wrist ribs though. I'm very certain that was just to make putting the costume gloves on easier. It's also not my prefered look as it makes the alien look too much like a b-movie monster. The ribbing pattern doesn't seem to serve a biological function, and doesn't look natural to me, even for an alien, so I'll stick to the elegant sculpt of the wrists as is.