Weston or Westin are both fine, though I prefer Weston--it seems more intuitive. Please not the Y.
Weston and Hudson are great together. I agree that Westie is a super cute nn.
Griffin and Hudson are awesome together as well.
Griffin Hayes sounds slightly better than Weston Hayes, but both are fine. I don't think the "haze" thing is a problem--especially since it's a mn.
I think Hudson & Weston sound fine together. I don't think of "haze" when I hear Hayes, I think it's cute. I like the idea of having the two "H" names for the two boys as well. I think both are great. Don't care much for Griffin personally, but do whatever you love!
I love Weston and wish my hubby did! Love nn West. And I think Hayes is super cute, I was wondering about the "Haze" thing too.
Hudson and Weston are a little close for my tastes. As an aside, I'm personally not a fan of the more kree8tiv spellings (I would think it Westyn was the name of a little girl).
Hayes is a great name with lots of history (and a presidential surname!)-- but I have to say Haze is really bad. Haze (not Hayes) fails the resume test, blind date test, and supreme court justice test (and I'd assume a drug test lol).
Griffin is a great name.
I like Weston, although I prefer Wesley (which would get you away from the matching on endings). I think the bigger thing is that if you have another son, I'd kinda find it strange if you veered too far away from the pattern... Same with Hudson and Hayes... you now have an H pattern. I do think of Haze... pollution. However, I'm in China (very polluted). Westyn I do not like... there was an article saying that 'y' is not a super vowel, as some seem to think... I kind of agree with this. An unnecessary y can look a bit eweneek.