I don't really see the "inconsistency" in art all too much, I think maybe it just comes down to practice in improving line art which will come down to experience. Maybe looking at references just to smooth out certain things, hands are near-universally tough, maybe general consistency/symmetry in limbs or proportions. I should mention that a tip I find helpful is mirroring my images just to quickly catch any imperfections.
I agree with the colors. Especially in some sort of clown world, at least the bright, bubbly characters deserve a little more punch and vibrancy to compliment them.
I think based on your descriptions, your characters are pretty effective/apparent in their clichés. I'm intrigued in how you will implement your satirical elements, as I think a satire especially will ultimately have some more reliance on writing, imo, more so than other works. It might require some more thought and self-awareness. But thus far, interesting 