Who should I cosplay as?

Okay well I just bought a super long blue/black wig, but now I am going to a con and there arent many characters I can cosplay as with it. My two friends are going as kairi and namine from kingdom hearts, and they want me to go as a KH character too (Xion, probably). But the issue is, I only have 100$ to spend on a cosplay and if I cosplayed xion I'd have to buy a new wig and a costume. My other options are either Hikari hanazono from Special A or Konata Izumi from Lucky Star. I want a character that is well-known and will be recognized. Who should I go as?