First of all, I don’t think you’ve got a problem with any of these names with your last name. Some things to consider might be whether you like or dislike the double L in [name_u]Callum[/name_u] and Brightbill, and the same for the repeating short and long i sounds in [name_m]Gavin[/name_m] and [name_u]Finn[/name_u]. I’d personally discount [name_u]Beckett[/name_u] as you’ve got the repeating B and T there too!
I like [name_u]Callum[/name_u] and [name_u]Finn[/name_u] best, myself!
[name_u]Finn[/name_u] Brightbill is stunning! so handsome and fun.
[name_u]Beckett[/name_u] Brightbill is gorgeous too, I love the alliteration, makes it very memorable and cool sounding - like the name of a main character in a novel!!
[name_u]Declan[/name_u] is lovely, too!
I really like [name_u]Callum[/name_u], [name_u]Finn[/name_u] or [name_m]Donovan[/name_m] with Brightbill. I think I like [name_m]Donovan[/name_m] Brightbrill the best. [name_u]Declan[/name_u] is nice too though.
[name_u]Callum[/name_u], [name_u]Declan[/name_u], or [name_m]Gavin[/name_m], I think. Very cool last name, btw! The only one I definitely would not use is [name_u]Beckett[/name_u], way too tongue-twisty.
[name_u]Beckett[/name_u] Brightbill is fantastic. The alliteration makes it so memorable. I also like [name_u]Declan[/name_u] and [name_u]Finn[/name_u].