I see many wonderful ideas over there! Are you suggesting adding a skill tree for each tribe? That would be great! like each unit type of each tribe has different base stats and you get points to upgrade them in a different direction this will make the game more versatile but may pose a balance issue (tweak work?)?
But to be frank I think the developers may not implement any feature suggested by the community as this game has a dwindling player base. This game is a business and needs money to run it.
To the developers, popularize the game is the first step before making this game more interseting .hope it can better !
There is many ways to do this, either skill tree or what I would prefer have upgrade paths in for example academy, you have 1-3 choices which unlock troop or upgrades etc. and locks the other path.