The Rocketeer was a fun little movie but it had its flaws too. I certainly don't think there's any harm in a new version, and potentially a lot of good could come of it. And if it's awful, well, that hardly means the original is any less fun.
(Talking of Disney movies of that era that are ripe for a remake, how about Dick Tracy? I actually really liked the 90s film for what it was, but would love a remake.)