Nexus of the World
Crap, I forgot Batman still wears external panties. But he looks perfect in Batman Begins without them.
I think it's a matter of what looks better on film doesn't necessarily look better in comics, and vice-versa.
That said, in Asia, big bright costumes like this are loved.
I also think the overpants remind me more of ancient Greece and Rome, as well as the circus strongmen and bodybuilders of the early 20th century. I think that connotation is important to keep.
When people remove the overpants he seems, at least to me... less. The serendipity, the mythical innocence of the character fades and he becomes neo and stylised and 'cool'. But I don't think a cool, modern costume is what Superman, as a character, would want to wear, and I don't think it's appropriate for him to do so. I think whenever Superman appears he shouldn't become a 'cool' guy - his presence should make you feel like an excited kid again. All the redesigns of Superman seem to lose this, while people who stick with the old one seem able to capture it (though, not always).
It might be possible to improve on it, but I dunno. I really like it, and I don't honestly find it stupid. Little kids who dress up as Superman don't care about it either. I think people make a bigger issue of it than it really is.
But back to my point about film - one of the reasons an unknown was cast as Superman back in the 70s was because Warren Beatty spent a day in the Superman costume and turned down the role. It became apparent no star could wear the costume without looking stupid. An unknown however, seems to work. On film, redesigning Superman's costume to remove the overpants is like getting rid of Wonder Woman's star panties. It can work quite well - but because live-action films are a wildly different medium to comics. While a change would suit the film, it doesn't mean that change should automatically be spearheaded into the comics medium unless its warranted.
So, I like the overpants a great deal. Just on a colour scheme, it breaks up the costume really nicely.