That's quite simply how it works with most games. Generally, players most familiar with a game will always have the best potential for good map design, regardless of what game it is. Sure, anyone can just place down a few dozen lv 10 good Horned Reapers or something, but challenge is almost never a direct consequence of good design, and vice versa. I think I'd usually take good design + lacking challenge over lacking design + good challenge.
Yeah, I thought so. It's actually a really decent map - definitely one of the more challenging ones I've experienced. You could have given me a Prison and Torture Chamber in that map and I would likely never have used them. Most things that are typically powerful for players are no where near as effective under constant harrassment with limited gold. Having no gold pretty much nullifies any rooms or spells that can be considered overpowered. I'm going to go through it again, but this time walling myself in for a much longer time.
That's still a lot of micromanagement though. There's also an increase in upkeep costs which can make quite a difference. But yeah, I admit it's not really much of a deterent or downside. There are lots of elements that can be played with to reduce its effectiveness though, such as giving converted creatures/heroes higher wages, having them stay angry once they turn to your side (never made sense that a torture victim went form ultra mad to instantly happy), having them slowly anger in the lair or hand (like Horny), introducing more creature-hero rivalries, etc.