They can only get 6 classes max, so not really. They can only be Dread Fighters, Dark Falcons, Vanguard/Great Lords and Grandmasters along with Lodestar and Ballistician/Witch. If you wanna make Ike or Marth or Robin sick Ballisticians you can go ahead and try since the class supports itself with skills (sorta) but they will never have the potential of the other units even if they get personal stat modifiers.