Rain.
He's royalty and uses aquatic abilities in battle - he's literally the Aquaman of MK(automatic win for me). Really hope his lightning move isn't as slow as Nightwolfs - or has different properties... I seen the Kenshi redesign, so I'm hoping that he has the UMK3 costume instead of Armaggeddon's poncho...
P.S. - (I'm a big fan of any water-based based characters: Aquaman, Rain, Hakan, Shipwreck, etc.)