Seven Of Nine, and it's not even close.
Boring, bland character, catsuits and hairdo that for me undid the obvious "sexualisation" they were going for with the character.
If they had put her in a starfleet uniform with her hair down and allowed just a modicum of personality, then maybe it would have worked, but the character just failed on every level for me yet still became a pop culture icon that transcended Trek.
and i still can't figure out why
Ask any 14 year old boy and all will become clear.