Also, attrition seems to be a major focus, and possibly also a major concern of balancing. The "health/mana on kill" properties, as well as the "life/health stealing" properties, are very powerful in this regard.
The game does not seem all that difficult in regards to action, since the most difficult encounters, bosses, can be briskly walked away from (as long as you leave an escape route), leaving you time to ponder how to deal with them (though you could also just pause the game, I guess). For regular enemies, action-skill on the player's part can help decrease attrition, and so can figuring out how to have as little attrition as possible (also by using tactics). One challenge is to have as little attrition as possible without specializing for attrition-decrease at the cost of being able to deal with bosses.