As for his blue arms, yeah I do agree that the color balance with tan arms works better for the games, especially the classics where his arms would be really hard to see if they were blue, since they'd blend in with the rest of his body.
However, I do like the look of blue arms in general because it just makes more sense. Why do his arms look hairless normally? Especially compared to the other characters which generally have arms that match the rest of there fur. I think Sonic Boom pulled off blue arms on a modern Sonic design really well tbh. But on the whole, the color of his arms doesn't really matter to me either way, I think he looks good with either color.
His separate eyes I think add to his cuteness in the movie, and would be interesting to see in the games even though I doubt they'll do it. The only other characters with uni-eyes are the other hedgehogs though, so if they did want to make the change there'd only be a handful of others to change as well.
A bigger part of his cuteness however, is his pupils. There much bigger in the movie, and I think that is key to making a cuter Sonic. That, and his eyes take less space on his head than in the games, which I also like.
In conclusion, I think my ideal Sonic should take elements of the movie design, but also keep elements of his game design. Let's say he keeps his tan arms and connected eyes, but gets slightly smaller eyes and bigger pupils, as well as being shorter in height. I'd love that.