Wowza! Real tongue twisters! I have a Carson and a Dawson and often call them Darson in a fluster! If you like the rhythm of those names with the "y" spelling, than Dylan is real cute! You could choose Dawson and spell it, Dasyn. I believe this is a Native American spelling, but it does follow your theme! :)
Please consider traditional spellings, as it will drive your kid crazy to have a name that everyone automatically assumes by the way that it sounds, is spelled one way, and is in fact not spelled that way. (For example, everyone in the universe will hear Davyd as David. You run the risk that by the time little Davyd is 12, he will probably inform you that his name is now Jack.) If you want more creative or unusual names, that's great, just choose one that is creative in its normal form, like Dorcas or Logan. Dylan is a very handsome name, and has what you want without anyone being confused by the spelling. If you like the added y in words, look up some Welsh names. Have you heard the name Lael? It's quite a pretty L name.
Like david lee.(was my uncles name) like dawson or lawson