I honestly favor Sook's design, save for Lightning Lad, whose costume is a little too busy, I think.
The older designs aren't bad, not by a long shot (save perhaps Chameleon Boy) but they truly scream 60/70's vision of the future to me, which isn't exactly inspiring, save in books I read as a kid (Valerian and Laureline, Yoko Tsuno, mainly) because nostalgia is a huge factor.
Honestly, the comparison makes me want to get the new LoSH books more now. If only to see if Bendis will add new characters.