CLOWN - inspired by Senor W. but not him of course, he's one of a kind
Clown would be an acrobat, a master of disguise, a trickster and a disarmer. His (or her) character would be bright and sunny but would hide a tragic, secret past.
And why not make Clown the Asian legionnaire? I'm tired of Asians being martial arts experts or dragon-somethings. Preferably he would assume the name "clown" in his native language, just for variety's sake.
I know there's Harley Quinn, or there was Harlequin the Joker's Daughter in the 21st c., but not sure what her powers are.