10
Also the beyond ze dark portal orc campaign is lacking in terms of heroes in missions I don't think anybody will say no to having grom hellscream in a couple more missions aside from gorefiend the orc heroes only show up in 1 or 2 missions , kargath could appear in the missions against kultiras , dentarg in the alterac mage mission , and gorefiend for the blackrock spire rescuing dragons mission
Also orc heroes suffer from lack of healing so having all heroes orc and human alike get regeneration is good idea , age of empires 2 had a similar issue with heroes until the expansion pack came around (the conquerors) giving heroes health regen made it much better experience allowing you to use heroes more freely without fear of losing them
Grom and kargath are the same so how about granting kargath some +10 health and 1 more attack while grom gets +2 attack , human heroes are very different from each other and their appearance again and again throughout the campaign made it a much better campaign than the orc one in my opinion the assault on shadowmoon fortress lacked heroes but its mentioned that khadgar and tyrlaoyon (I messed his name up I know) have searched the ruins of the fort so having both replacing a knight and the starting mage will suffice a lot of little changes could be made or additions to the campaigns that would make them a bit more interesting.
ALSO some more color variety would be cool playing as the warsong or shattered hand or even the bleeding hollow , and the bleeding hollow could get a bit harder they are supposed to be this legendary orcs in game they don't upgrade much I would say they gotta be on the same par as the warsong in terms of unit quality (the warsong gets lvl 4 units most of the time) however their attacks would rely more on grunts/trolls while the warsong would be more ogre/catapult oriented.