Hey Gun metal
Wild West is a complete game. Character creation is based on the d20 Modern rules system, which means characters pick a character 'type', i.e. Strong hero. This is where character progression comes from, hit points, skill points, etc. This also gives you Talent trees which progress like feats. The player then chooses a vocation, i.e. Lawman, which have additional Vocation skills and unique Talent trees (feats).
Designing alternate Vocations for, lets say, Acrobat/Entertainer should be pretty easy. It's the talent trees which need some thought/imagination.
Good luck with your game and have fun.