I am designing a thing which started off as a near-retroclone-- bolt Player's Option mechanics onto a BECMI or d20 frame-- and which has slowly drifted further and further away from the design goal of 99% D&D compatibility. (This is the same system I am thinking of applying to Galactic Dragons and Shroompunk.) One of my core mechanics for the intended level of PC customization is three tiers of character widget awarded every X levels. Proficiencies are... well, proficiencies. Weapon and armor proficiencies, skills, weak 3.X feats. These are awarded every level. Learning spells from your own class spell list would be proficiencies. Feats are beefier. These are the good 3.X feats or toned-down 5e feats. These are awarded every odd level. Learning "general" spells would be feats, or learning spells from a different specialty within your class. Learning combat styles or martial arts would be feats. And then there's "options", which roll up all of the subsplats of modern D&D: subraces, subclasses, kits, themes, Prestige Classes, Paragon Paths, and Epic Destinies. Figure you'll either get one or two (one race, one class) every 6th level, but I'm still working out the exact numbers. Question is, what do I call "options"?