Lots of typos, the pathing issues mentioned above, excessively long waits between waves, and the tower deployment UI needs work. Suggest taking a look at how other TD games handle deploying multiple towers of the same type; would remove a lot of the frustration from setup, as well as the need for long waits between waves. Good core, but needs work.
A setting allowing the game to automate combat by using the highest attack that still has above a player-set % chance of hitting would eliminate a lot of click-wait-click-wait-click-wait annoyance.
The non-artifact randomly-generated loot is nearly always worthless except to sell straight to the store, and it would be nice if this were not the case. Additionally, healing spells should be castable outside of combat.
Seconding the Auras not going away bug. Am currently sitting here dying slowly to a purple deck with a strength-1 card and an eternal Enforced Silence that the opponent played. Now that's infuriating.
I thoroughly enjoyed the first difficulty level, but thought it was a bit ornery and a bit un-fun to make one particular upgrade (Antimatter Shield) mandatory to get anywhere in General.
The final boss is just silly. Three minutes of bouncing a steady stream of missiles at him seemed like a bit of overkill. I could just be bitter because the badge didn't trigger, but I think the hitpoints on the bosses are genuinely set an order of magnitude too high on 30-50 for General.
Game could have been interesting if it was a different game. Also, timer does not appear to count down accurately in "Survive x minutes" objective levels, which is just adding insult to injury.