We live in an era when most designers have noticed that we like to control what our characters look like as well as how they play, something City of Heroes knew a long time ago. But City of Heroes had another cosmetic application that gets forgotten; it took a while to happen, but you could change the way your character’s powers looked as well as your costume.
This is one of those things that I’m surprised hasn’t been copied more often. One of the things that drew me to Inscription in World of Warcraft was the promise of making visual changes to character abilities; it might not have largely lived up to that promise, but I still love the changes you can make. And why should we stop there? Why can’t my Dark Knight in Final Fantasy XIV have abilities that look more holy rather than void-touched? Why can’t I give my Sith Warrior some lightning animations in Star Wars: The Old Republic just for visual effect?
Of course, I know the actual reason why has to do with a lot of technical work for little mechanical gain, but it still matters. Heck, in some cases your abilities are more visible than your outfit, and yet they’re less mutable. What cosmetic changes would you like for your character abilities? Would you like to give your Paladin some fel fire effects in WoW? Do you want to be able to use dual pistols instead of a rifle in The Secret World while keeping the rifle skills? Or are you happy with the options you have?