[Suggestion] Trainable units can earn XP
Originally I noticed that only your SOV and hired heroes earn XP but your other units didn't. So I reported it as a "bug" which got a reply that trained units were cannon fodder and not suppose to earn XP. But honestly I think this is a mistake as a lot of TBS games have your units become more experienced the more they fight. Most are simply Normal/Veteran/Elite which is fine as it adds another interesting layer to the game by helping reward players who focus more on strategy and keeping their units alive compared to someone who simply zergs with superior economic power.
In the recent build 0.302 I noticed I was able to train Veteran units which take 1 more turn to build but don't have any higher cost otherwise. They do however have 12 HP instead of the normal 10. So why not all normal units to become Veterans through XP? And they could continue up the promotion line to elite and whatever other advanced quality types are in the Military tech tree. Though with the use of levels they could simply make it a level bonus and veterans, elites, and etc start at a higher level.