This is beautiful.
It reminds me of one far eastern technique of drawing dragons:
It’s fantastic 
And this…
Yaknow… seeing that video… I’m thinking I must have seen it or something similar before, and that’s probably what subconsciously inspired me to model the brush as a chain of spheres… 
Give us the infinite long string of balls pls 
I won’t stop you! number of spheres is just a constant, but as the chain length gets longer the simulation slows down… so would take some tweaking to really support looong chains.
Here’s the glitch if you want to remix it/mess with it.
If anyone does anything cool with it though, I want to see!
(segCount is the number of spheres… you can crank it to 100 and it still mostly works.)
Super nice!
This is cool
Maybe you should considering adding customisations for colors.
Ctrl-R selects a new set of colors.