Looks good to me. Doesn't change tiers around too much as compared to JaronK's system, sums up a lot of what we already know about classes.

Funny thing to note: it's basically impossible to be a pointless one-trick pony. By the time you're pointless at your primary shtick, your secondary abilities are so close behind, you might as well be a generalist (cue amazement: it sucks in any way possible!). I mean, unless you design a class that literally gets worse at everything besides its primary ability (like a commoner with -class level to all d20 rolls except melee attacks with a shovel).