Here are my ideas for improving the training hall:
-Make another place to fight enemies. Honestly, I've seen people go in there and clear the entire thing with one Calibur charge attack. Make it bigger, and maybe add a second one, with more enemy spawns.
-"Scarecrows". The addition of invincible (or respawning) dummies of different types (one gremlin, one beast, one fiend, etc.) will make the TH better for weapon testing, which will mean that I don't have to spend 10 energy to find how hard my new weapon will hit.
-Make a room that lets you test armor against different enemy attacks. For example, maybe one separate part of the new TH would be full of lanes, on the end of each one is a bullet shooter (like the turrets in Ironclaw, only non-explosive bullets). One land does piercing, another shadow, the third elemental, and the final just normal damage.

My goal with this (other than making it a future update) is to make the Training Hall better suited to higher-level players, so that more than just newbies get something out of it.