My preference goes to words. Organized by themes, as seen in City of Mist, Otherscape and Legend in the Mist, it's ideal. But the simplified version one could see in Lady Blackbird works, too.
Framed like that, character evolution takes another meaning, one that I prefer, because it feels real. The characters evolve, they change with the fiction, according to it. They don't simply get better with more skills and powers and better stats (and often they don't get better, they simply change).
The "concept" of the Cypher System is a bit barebone but quite handy if you're in a hurry: I'm an adjective noun who verb.
Otherwise, when I want to play a fantasy story of small characters who rise up to the challenge, zero to hero, in other words when progression, rather than evolution, is the goal, classes and levels all the way.