Looking at the released screenshots I noticed that one hero units was classified as 'scout' and had the ability 'falcon' (just a guess but better LOS?). The other hero was classified as 'knight' and had the ability 'charger' (I assume that one is a combat ability). They also semed to have an inventory above their xp bar.
Now assuming that 'scout' and 'knight' are classes in the game. Which other classes and abilities would we like to see? How should our hero's progress? What traits could they have?
For example I could see the 'scout' progress to 'ranger' (say when he hits level 5 he must complete a quest that turns him into a ranger) and gets an ability like 'lay of land' (more movement points per turn). This would now make him the ideal leader for a raiding army (light calvary horse archers, think Atila the Hun or Gingas Khan) built for speed.
Conversly the 'knight' could progress to 'paladin' (after completing the quest that will turn him into one) and get an ability like 'rallying cry' (temp xp boost to your troops). This would make him the guy you want running a large heavy hitting army.
I would like to see is your avatar (as sovereign) guide or influence the class your hero starts out as. Since you have to make a magic investment on said hero you should be able to decide what class he/she is. As supposed to you find this individual who becomes a 'knight' when what you really need a is a 'scout'.
From the screenshots in what I assume to be the inventory bar (above the xp bar) both hero units have a close book and blue glowing bottles. Now I will go out on a limb and assume that the book is the spell book and that those are mana potions. If it is that hero's spell book it would imply that all hero’s will have some casting ability. This would make it a trait that all hero's share (consequence of the magic infusion your character avatar them?).
So knowing that all hero's have at least one ability, assuming they can cast spells and that they can level up this are some classes that could be in the game:
Acolyte -> Cleric -> Archbishop
Ability: Morale related?
Spells: Life school?
Sage -> Oracle -> Prophet
Ability: Combat or defense bonuses (since they can 'see' what they enemy will do)
Spells: Scry or any 'espionage' line spells that reveal enemy information for you.
Mage -> Wizard -> Archmage
Ability: Use of magical items and magical defense
Spells: Maybe based on the schools you follow?
Thief -> Rouge -> Assassin
Ability: Stealing enemy artifacts or magical items.
Spells: Anything that increases that ability of the hero or its army to 'sneak'.
Any other ideas?