Awesome feedback!! Thank you so much! I might continue on, though it's not a very traditional game and difficult to see go anywhere, but I will take a look at the resources you mentioned.
That's what's so great about the idea! You don't really need more mechanics than this either, the "body shutdown" and helper neurons is more than enough to build on.
The game doesn't need to be balanced or paced either. It can be "gradually build and maintain a large and beautiful geometric construct" and the reward the player gets is taking a few steps back and watching what they've made. That's also why you need to have screenshots in mind. Not as a functionality, but practically; think about how the game is framed and how it will look statically on a screenshot, as that's where much the strength of this design lies. After playing for 15 minutes seeing the structure from inside to then flying away and look back felt satisfying to me and took a photo. Not only because the structure was so beautiful (it looked like a sitting fox), but because it's also ephemeral. It changes, it doesn't last, which gives it even more value and beauty.
This is also why I suggested to scale back on things, that might sound counter-productive and non-intuitive with how "simple" the game is but I really believe the lines and dots can speak for themselves with some clever design decisions. Focus on the experience and emotions and not the balance and math of it.
Another suggestion I forgot to mention is "hapticity". Instead of clicking and selecting, make it "physical". Make connections between neurons something you "draw", something you "drag" between them that gets more resistant the longer the distance is. Make creating helpers a physical act of pulling the neuron out of the pattern and releasing it.