These are good shapes. I think your main trouble is deciding where to put the little double barbs:
Left side of the first vertical of most letters: normal.
Making diamonds on the N: clever.
One on the thins of V and X: okay.
Right side of M and W: unusual, unnecessary, but potentially defensible as a sort of bracketing device.
Right side of other letters: hmm, no.
Clustered all over the middle of W: what, no.
Z: It's more of a tail than a structural vertical, so still a weird place for them.

Moving on to overall letter form, Y is where you seem to have lost the plot. It's cut and pasted together a bit hastily as if you have no historical references for the letter Y. The inline element is reversed. Then with Z, you reverse the stroke angle on the bottom, which is sort of interesting but makes the thin line look even more out of place. Keep drawing.

Great. Do you think the curves are smooth enough?

Yeah, you have smooth curves well in hand. The curls are super. I see a little awkwardness in S and the tail of Q, but I think that's more a matter of weight and composition, not smoothness.

Hey I completed the set. How does it look?

I don't see a newer image. I really like the set shown in the May image! I agree that the tail of the Q is too plain; it just sort of rams into the body of the Q. Maybe an overlapping swath, such as appears at the bottom of many of your vertical stems (like at the bottom of B)?

(duplicate because of Typophile server problems)