I am Canadian and live in a rural/working class area, so my opinion might not really count. But I love Winter. I have recently suggested it to my hubby actually and he is mulling it over. Anyway, Winter doesn't seem like a classy, better than working class name to me. It just feels really fresh and down to earth.
I love Winter! It's my daughter's second middle name - Cornelia Hermione Winter. We chose it because it honors a Winn plus we both like the sounding and I was born in winter. Cornelia was born in May so I think it works not only for winter babies.
Felicity Winter is beautiful and although I love Winter, in your situation I would use Felicity Eve.
I love Winter in the middle spot! I actually considered Hazel Winter when I was pregnant with my DD (Who is Hazel Naomi) because most of our family are born November - February so we thought it would be cool! But Naomi won. Poet Winter is my favourite Winter combo, but it's on my GP list for obvious reasons haha!
Felicity Winter is really pretty! I would love to encounter a little Felicity Winter.
Winter has been my favorite girl name since 2008! So sad to see it's gotten into the top 1000 this year. :(