Alright then, I'll put this idea out for discussion: Tiles with a lot of buildings.
They take forever to get through! It makes sense, but they also have as many as like, 3 henchmen, even before Demonaica has caught on to you. Now while henchman spawning is another subject, I would like to suggest adding shortcuts after you finish a building. Dying after getting far in these tiles just sucks a ton, as it takes a lot of time to get through them. Even one building compared to none can double the amount of time the tile takes to purify. Also, being able to skip these buildings (via extreme mobility) is...extremely desirable because it saves a lot of time. I don't know if this is the intended effect, so I thought I would also mention that.