Since Lucina was originally going to be a Marth alt, that means Marth probably doesn't have one either. Same thing with Mario and Pit since Dr Mario/Dark Pit were probably originally alts as well before becoming clone characters.
I still expect some of the obvious choices to still get in though. Bowser will probably get a Bone Bowser alt, Peach a Daisey alt, King Dedede a Masked Dedede alt, Toon Link a Pajama alt, Ike getting his old Path of Radience design alt, and Pac-Man a Mrs. Pac Man alt as well. Plus according to the rumor that Bowser Jr has all the Koopalings as alts, Olimar is suppose to have Alph as an alt custom as well.
So I wouldn't be surprised if we still get several others alts in the end. Hey, at least we only have to wait less then a week now to know since the early Japanese copies will start leaking around Monday.