I was actually worried about some of the monsters (notably the Hydra) being too weak and dying before they could do much of anything if the heroes ganged up on them: The Hydra and Kraken were particularly worrisome.

Perhaps you could suggest where balance points might lie, either by improving the hero paths or weakening monsters? There is a reason I called it an Alpha stage of design.

I would think you need to improve the hero paths, mostly because I think having the monsters having such vast powers and arrays of abilities is suitable. I don't really have anything to suggest at the moment, though. I still need to read up on Theros itself one of these days.