Lord Zurgling said:
I really like the idea of "Mini wizards".
Warrior hero can "challenge" other heros to a duel (the respective units still fight) while boosting units abilities
wizards can cast weak lore abilities every turn that affect their unit
clerics can do much the same
rogues should have a movement based ability
I also quite like the idea of legendary units like dragons: tke up your creature and guest slot but you get a red flag fire breathing monstrosity
Or a wizard (or other classes too) could hold on to an extra lore card for you, but there would be limitations. Like max lore cost of the card (this could be raised for a higher level hero) held and/or card playing limited to movement/attack phase.
all in all if heroes would have multiple abilities they should be minor and not overshadow the warcouncil.