Alright, here are some more costumes and their pics you can put in the OP.
Cowboy Luigi (plus the angry eyebrows)
OoT Impa Sheik costume (give her a bunch of bandages wrapped around her mouth if she needs to be censored)
Ordon Villager Link (with sword sheath, Ordon Sword, and shield)
Twin Snakes Solid Snake
"Iroquois Pliskin"
Also, here's an image you can add for Draw Dedede, as he hasn't got a picture for it.
Finally, its my opinion that the section dedicated to just Pokemon in general items be just removed.
The ideas are pretty obscure to somebody who hasnt played every Pokemon, and the Pokemon have enough ideas to fill all their costume slots, if necessary.