The only one I firmly disagree with is 1990's Alan Scott. The late 200's Alan Scott ("look, I'm a human lantern complete with a handle") was by far more hideous.
On the fence about nu52 Superman. Honestly, I got used to the missing trunks...and now that they're back I don't care for them. I didn't like the armor element of the nu52, and just thought they should have made his pants a shade or 2 darker to break up the continuous blueberry look.
I'd also argue Donna Troy's first Troia costume (by Perez) was pretty bad. Looked like a clown vomited all over the stars look. The later streamlined versions worked a lot better.