I would say his height was part of his character. There is a great panel from Wolverine's solo comics, with him face to face with Juggernaut. It just makes him more bad**s because he was so short, but pretty much indestructible. So he doesn't have to be some imposing figure. I still prefer a shorter Wolverine. It lends more to his grit. If he himself is imposing and towering over people then it is just another muscle bound tough guy. He "stands" out, pun intended because of his diminished size. He is still musclebound but short. It has to do with the whole don't underestimate your opponent thing. Which plays well with a short guy going up against these super powered mutants.
As for dwarves, they are fantastical beings, so I prefer the fantasy version we saw in The hobbit and lotr. They look stout, where as real little people don't. The proportions of fantasy characters are different than real people. So we have the technology to make them now. You can still cast whoever, but I prefer the fantasy version. Dwarves with thick forearms and legs, and a barrel chest. Again they should look stout and hardy, which I think lotr and the hobbit pulled off. Oh and the nose and beard is important, but that is a given. The hobbit movie did not do this for a couple of dwarves which hurt the aethestic to me. I think Balin and Gloin were probably the quientissential look of a fantasy dwarf. The others might have had something I though was off, but those 2 I remember being ideal.