After using some T&T solos for some initial playtesting, I'm really happy with the way this is shaping up!
Tonight I re-wrote the fighting section in order to clarify how it works. I also brought back the clash as a roll-off between two sides!—but only in the case of PVP conflict.
One thing I'm excited about with these rules is that they are scope-agnostic. You could have a military unit of 100 fighters statted up as a follower, command them to fight 100 monsters—or 1 colossal monster—and resolve it the same way as if you were a lone delver fighting a single living skeleton.