i guess it depends on what you're looking for in terms of "best outfits". i like the embellished, yet believeable style SNK gives it's characters versus the more realistic style in VF4/Tekken. Of course that's not to say that character designs such as Akira, Pai, Lau, and hell... half the original VF crew don't hold special place in my heart. With the exception of Aoi and to a lesser extent Taka, the character designs took a different turn after VF2.
There's too many jackoff outfits in DoA to make it a serious contender in the above category for my tastes. (See the Kasumi overalls pic below for an example.) Or maybe the female characters' breasts are just too oversized in proportion to the rest of their body to make their overall look cohesive. As much as i like DoA as a pick up and play fighter, the blowup doll female characters do nothing to validate the game's attempt at realism, whether that was the intent on any level or not.
In terms of choice, 3D characters will always have a better selection of outfits because it's more or less a matter of simply changing polys and textures versus drawing a complete set of sprites. But i think overall that 2D characters' outfits look better, specifically SNK's.