I think
Dashiell is really fun and spirited! Dash is a cute nickname. I would use it, yes, in fact I should run it past my husband one of these days.
Dashiell ReidDashiell AmbroseDashiell EverettDashiell Montague :) over-the-top, perhaps
Dashiell BramDashiell RomanDashiell GreyDashiell MarloweDashiell Monroe
I've never actually heard someone say
Dashiell. Is it DASH-ee-ul? DASH-yul?