Playing this on single player, and I have a few issues (some of them the same as above).
* Respawn is problematic in higher-tier areas, you can't get out and you can't go any further because the creeps take so long to kill (and in one case, they respawned right on top of me). Perhaps you could pause respawn for an area while your units are still in it.
* Abilities don't really scale well with dungeons or monsters: either they're so broken it's hilarious, or they might as well be level 1 for all the good they do. The Necromancer's skeleton is a good example of overpowered at first, and then underpowered by the time you get to the skeleton cave.
* Some discrepancies with the text: the quest giver asks you to kill Adult Ice Spiders, but they're called Giant Icy Spiders. The Poison Bolt also says it does damage over time, as opposed to seconds.
* Some hint as to which quest giver does what would be nice. I'm assuming Willy the miner and Giacinto the Paladin have quests to give, but thus far they haven't responded.
* Units have trouble with the way gates; they'll head for one, enter another, and give up and walk the long way to their destination.
* I didn't have many problems with creeps chasing for long distances (if anything, I was trying to get them to tail me so they could get slaughtered by the town guard), the problem is from how far away they get reinforcements. It took me five tries just to kill the front guards at the southeast city because the hydras keep showing up and summoning dragons as well.
* Serious imbalance in the creep difficulty and reward: Starter creeps take a few seconds to kill and give 10 gold, while that giant pink Faceless One took multiple attempts to get its so-high-it's-invisible HP down, for a reward of... 47 gold. I get that you're supposed to get money from selling equipment, but that's just ridiculous.
* You should add more levels to the regular abilities, ten empty levels is just weird.
* Found the corpse item... what do I do with it?
* A bug with the Skeletons: at some point trying to summon higher-levels failed, and I had to get it killed to be able to summon them correctly.
More as I come across, but thus far far it's been quite enjoyable.