These look more like dark versions of all those troops and to me look really weak. Cloud balloons are almost just like regular balloons but have more damage, that's what the lab is for.
Just saw these ideas on google images :P Tbh id rather have a new troop with its own kind of special ability than a stronger archer or barbarian, just adds more diversity into the game
I agree with the others would rather have a newer unique troop than stronger versions to what already exists. Although i think Archwizard would be a good boss, or like the barbarian king roams your base.