Aside from colour, what clarity integrations were made to make the characters abilities readable? Surely having over ten abilities that are just 'magic paint' would be challenging.
We were excited about the potential of a paint mage because we can let Hwei paint abilities that can telegraph what he is about to do. Learning from Aphelios, we want to make sure the complexity burden is mostly on the person that decides to pick up Hwei. Thus, having the ability to make art of "something" really helps! While an opponent might not know exactly what a giant lightning bolt does, they can very quickly tell to get out of the way. The palette is another hint to what spellbook he has queued up.