Convention Costumes

At the end of this month, there's a convention here in town.  I thought I knew what I wanted to wear but now I've changed my mind.  I've changed my mind to undecided once again!

I was thinking that I'd wear this Harley Quinn costume that I bought over the summer (big $5 costume sale, it was beautiful).  

OR I could assemble up a super cute Franken-outfit.

OR I could class it up in style.

OR an unconventional conventionist.

OR baby doll Lolita.

OR the cyber rave girl.

Sooooo........  I'm asking for your assistance in this matter.  Suggest as you will on which you think.