i don't know of any other systems like what you're looking for off the top of my head, but i do have some thoughts that may (or may not!) prove useful for this if you'd like them?

why would i want you to? :3

i draw as a *very* casual hobby. i know i have plenty of areas that need improvement but this is my first project that i've taken seriously and i'm very happy with what i've been able to do so far