Altrough my MUGEN loads in 6 seconds.. It has 35 chars, and most of them have 10MB+ size... Oh, and the screenpack infludes too. Some big screenpacks take a bit more to load.
I dont actually know what you mean by cool, each person has their own way to describe a cool character. For me, cool characters are the ones with awesome gameplay & maybe some cool effects thrown into them, eg PotS' Geese