Right now, I'm including the character classes in each set. Spring has rangers and druids, Summer has fighters and wizards, Autumn has clerics and paladins (and necromancers), and Winter will have rogues and barbarans. If I continue the series beyond that, I'll probably do bards, monks, and psions, and maybe sorcerers in future sets. But they won't be Kickstarter Mystery Prize #9, that's already a specific thing. More likely I will put them on sale like I am these ones.
EDIT: Unless you're saying you need more variety than the 39 rangers in the Spring set, in which case, no, that's a lot less likely to happen. There's a near infinite variety for player characters in terms of style, armaments, etc., so I would never be able to create a set that included everyone's idea of what their ranger looked like—and that's not counting all the weird races out there. And at a certain point, it's just me wracking my brain for different ways to draw a ranger and coming up empty, and still not matching what other people might be wishing for.