Ohh I hadn't thought of storing signals like that, that's a good tip.
You're right that too clever can smell. Too terse also, like big regexes and clever one-liners. Don't ask why I know that :)
Tough question, how to make something easy to debug and remain extensible. The Godot State Charts addon is a good example. It comes with a GUI debug control, so internally its organization is concrete enough to build tooling for. But it's also very flexible to use, I think because it's not highly abstracted from vanilla Godot.
I'd love to spend more time on tooling, speaking of writing code for myself.