Quest mobs will spawn again after you've killed them if you exit to main menu and then come back to the dungeon. I also got a dungeon where either a quest mob didn't spawn, or it spawned somewhere that I was unable to get to. Mages are incredibly underpowered compared to warriors, warrior in the 90s has 25k+ physical damage, mage in the 90s has around 5k. The mage mana recovery passive and Mana Cell are worthless, maybe replace with a + willpower passive and a mana shield passive, x% of damage taken removes mana instead of hp.
Some more stuff:
Customizable casting order, so each player can choose what's best for them to cast first, second, etc.
A window where you can change the required status of you/the mobs and maybe other stuff before a spell gets cast, for example you could make it so Pyroblast is never cast if the mob is below 50% hp, unless you are also below 50% hp. This window could be opened by clicking on a skill that's on the bar.
Some suggestions:
Toggles for each tier of loot, instead of picking up only the selected tier and higher.
An option to wait until all cooldowns are up before starting another fight.
A way to sell something in one click, instead of two.
Tooltips for all abilities (including basic attack) on your bar, with the current damage displayed instead of a percentage as in the talents window.
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