Heroes
Vixen: To me, she is the prime example of a character that has everything but the stuff that turns a character into a franchise. She has a cool versatile power set and a cool look. The things she lacks tend to be on the story side of things. Villains, supporting casts, compelling motivation stuff like that. to me she's a very interesting clump of clay just waiting for some writer to do something interesting with.

Plasticman: He's weird because he's somewhat well known but, still rarely used. Part of me thinks He and a bunch of DC's other more light-hearted characters deserve their own earth.

villains

Giganta: I've always felt Giganta was a cool visual constantly searching for an interesting character. None of her origin stories have really done it for me. She's one of Wonderwoman's most well-known rogue's but I feel her power level really doesn't fit the status of a character who is arguably top four in WonderWoman's rogue's gallery. All to often she comes across like a character Diana should deal with rather easily. kind of makes your rogue's gallery seem weak when arguably your third most known villain seems to weak for the hero.

The Parasite
The most under utlized villain in Superman's gallery.