I think this is pretty awesome. I can only assume characters isn't listed because they're bigger unlocks and have a much bigger entrance. Minions, Costumes and Icons all sound interesting.
I'm pretty sure these Unlocks are for each character, hence there not being an "unlocked characters" counter.
Atleast that's what makes sense to me. Why would I want to see the overall costumes unlocked to all characters? These stats should only apply to the one character viewing them, since this was a free for all match.