Wolves Den itself could need an upgrade to allow testing of mechanics/skills easier. Like a team duel would be important to check for bugs on support skills easier.
A dummy that deals 10% of your max HP as small aoe around it once you attack it, would be useful too. An area to test out rival wings mecha and other siege cannons etc. would help aswell. It is a pirate ship theme already - why not have a minigame there when you have to wait in queue.