I've played through twice so far, as a singleton Infiltrator and as a Lifecrafter. The Lifecrafter battle with Monarch was much easier for me but more than doable for the Infiltrator. Granted I played the second game as a lifecrafter who knew he had to spend enormous amounts of skill points on leadership and mechanics to make places like that easier. Ahem, but I digress...
As an Infiltrator, Monarchs pit and Matala were simply too frustrating for me. My lifecrafter made it through both pretty well though.
Jeff, thanks for a great game in the great Spiderweb tradition.
Edit: Yes I know Matala and the pits are optional. I just wanted to share my experience.