Troop experience. Is it necessary or not?

In HotA and WoG, they approached it differently - they created underground lava that gives a bonus to Inferno units, not Dungeon units.

Which, by the way, is more of a bug fix than adding a new feature.

This won't really save Inferno. The main problem is the weak starting army. Splash damage from Magogs, buffed Pit Fiends on level 114, 3 stacks at the start, Marusa's special ability - this really boosted the Fortress to a solid mid-tier faction. But, the original SOD is sacred, so my post is off-topic.

Added 5 minutes later
I won't vote. The topic really smells like trolling. Although, if I had the option to choose, I would play with experience.