Quinn JoachimQuinn AlessandroQuinn AmadeusQuinn Emmanuel Quinn Avery (how's that for unisex?!)
Quinn EverettQuinn SullivanQuinn Montgomery
As for the question of matching the starting letter of first and last names. I think it can work, depending on the letter itself. Some work better than others. Also, it depends on how many syllables the first and last names are. If you are comfortable sharing your last name (or give us the first letter and a 'sounds like'), I would make some fn-ln combos for consideration on the board.
Three boys nappin', one mama namenerdin'
To peruse my top 100ish names:
http://www.behindthename.com/pnl/82589
"My Inner Birthing Mother Paddles a Canoe" and other non-name musings
found on my blog:
http://jodifriesen.blogspot.ca/2014/07/paddle-power.html