Just a few ideas not saying we should get all of this.
A chagre bonus for orcs would be nice being at least 2x bigger then the other races some extra damage when they smash into a unit would be nice.
Orcs are big with thick skin a small arrow def bonus or small chance for the arrow to glance off of them would be nice.
Give goblins a small stat bonus when fighting near orc units to show them trying to keep up with their big bro's.
I'd slow down Ogres movement speed a bit but raise their def.
Goblins either need a higher unit size or be a .5 in the 60/60 cap.
A fast moving foot goblin bomber unit with no def or melee attack but makes suicide attacks and a high chance to set things on fire. Shooting at them before they reach their target may cause them to explode.