Trying to list those things
Barbarian <- Rage progression
Bard <- Song progression (the DC of the songs is not tied to the bard levels)
Cleric <- Nothing ?
Druid <- Wild shape progression ? Animal companion progression ?
Favored Soul <- Nothing ?
Fighter <- weapon focus and specialization
Man at arms <- Most challenges are tied to Man at arms level
Monk <-Fist damage (stunning fist DC is tied to character's level, not monk levels)
Paladin <- Smite progression
Ranger <- Animal companion progression ?
Rogue <- rogue bonus feats at level 10,13,16,19
Sorcerer <- Nothing ?
Spirit Shaman <- Chastise spirit progression (
Swashbuckler <-Nothing ?
Warlock <- Nothing ?
Wizard <- Nothing ?