So, this most recent session has been pretty standard. I'm starting to do two more weekly playtest sessions with groups not just limited to my current playtester pool, and in a different setting, so we should see the rules get bumped around a little.
One thing that I'm really not comfortable with right now is the fact that I occasionally have been making up things that don't have a place in the rules yet. One of the things that stands out to me as particularly lacking is the fact that there are no comfortably stable rules for environmental hazards and traps, which I was originally leaving out but should probably be codified: I make the players have a chance to roll a defense against them, and then it's handled like an attack.
We're also really low on status effects, which is not the end of the world (you can improvise them), but we should have standardized and codified ones.
I'm changing the First Aid quality so that you no longer need a dedicated tool, and the First Aid quality instead gives a bonus to the amount of health healed. This will bring things in line with elsewhere in the setting, and make healing actually feasible to pursue as a goal.
One somewhat fun thing is that the Unsung Gods setting has weird magic, and I'm starting to codify and shape it. It uses parts to build alien magic that doesn't always work in a predictable manner: the GM is supposed to have fun with it and make it powerful, but the immense cost and randomness of the effects give players a reminder that they're not in control of their newfound power.