Realistically, we're not getting much in terms of classic characters in a new DLC set, as they're saving that for a sequel.
Here's what I think after mixing my wants and expectations.
Awakening: Nowi (Tiki Clone), Gaius (Original Sword Moveset), Morgan (Robin Clone)
Fates: Selena (Mounted Bow), Silas (Xander Clone), Azama (Oboro Clone)
SD: Camus (Mounted Lance), Jagen (Frederick Clone), Merric (Linde Clone)
Classic: Alm (Chrom Clone), Hector (Original Axe Moveset), Eliwood (Xander Clone)