I would like to see “back-packs” available at the start of a dungeon that would allow different characters to fulfil different roles. I.e. a healer backpack that gives you 5 utility skills, or a tank backpack that gives you utility skills to taunt, protect etc. That way you can have any class play any role.
Either that or have a specialization trait line for each class that provides a healer/tank/damage utility role and skills.