Well today I learned we don't all look for the same things in a strategy game.
For me, working out strategies, making decisions and having to actually think is what gives me the "just one more turn" feeling. The game has to have clearly defined rules that work well together and a UI that explains them for this to work.
What makes tactical combat fun, for me, is figuring out how to form the right mix of units and using their abilities in the best way possible (think King's Bounty). Not just building a bunch of the most powerful units available in the biggest squads possible and then move them forward and click attack on the enemy. At the very least there should be some rock/paper/scissors at play here, but this game in its current state doesn't even have that.
Having a sandbox to fool around in was not what I was looking for. Not that I've really been able to play the game much with all the crashes and slowdowns anyway.