I think it depends on how each name sounds with your last name and how much you care about popularity/trendiness. Anyway, here are my personal thoughts:
Julian - [name_m]Favorite[/name_m] on your list! Soft yet solid, accessible yet with a worldly, international feel- plus [name_u]Jules[/name_u] is a great nickname. We considered it for our boy, but I just have too many [name_u]Julie[/name_u]/Julia/Julianne/Jules in my life on the female side, and I was shocked to see how popular it’s becoming for boys, so we personally steered away from this name, at least for our first boy.
Luke - Great name- short and sweet but packs a punch. Sadly though, I know so many, it’s losing its luster for me.
Gavin - [name_m]Can[/name_m]’t help but think of [name_m]Gavin[/name_m] Degraw, which gives this name a country feel (strange, bc I think he was more rock than country…anyway). For me that’s a negative, but totally depends on where you’re located and the feel you’re going for!
Everett - In the cowboy club with [name_m]Gavin[/name_m], but slightly less trendy and more bookish, which I like. Also, Ev is a great nickname.
Asher - [name_u]Love[/name_u] that it’s got history as an old Biblical name but still feels super fresh with the -er ending and [name_u]Ash[/name_u] for a nickname. [name_f]My[/name_f] second favorite on your list.
Levi - Also has a country/cowboy feel because of [name_u]Levi[/name_u] jeans, but I do like old Biblical names getting a revamp, and this is one of the best. [name_m]Can[/name_m]’t help but like it.
Chase - Feels like an athlete name, especially a baseball player, which feels a bit limiting for me. Also, I’m afraid the bank chain lends an unsavory taste.
Dawson - [name_m]Can[/name_m]’t help but think of [name_m]Dawson[/name_m]’s [name_u]Creek[/name_u]. If you’re not a fan of the show or have a good sense of humor when people bring it up, I’d steer away.
Beau - A little too much on the romantic side. I love [name_u]Bo[/name_u] though, especially as a nickname for [name_m]Bowen[/name_m], [name_m]Boden[/name_m], or [name_u]Bodhi[/name_u], and you have the added awesome nickname of [name_u]Bowie[/name_u].
Finn - Super cute and feels fresh, but definitely trendy.
Parker - Trendy, especially for girls now, but I do prefer it for boys.
William - One of the most solid, timeless names. You can’t go wrong choosing [name_m]William[/name_m], but I’d personally choose something less common.