I really like Max but feel like it’s too short to use as a full name/prefer it as a nickname. I’ve looked through the most popular Max- names and put them in a poll.
[name_u]Maxwell[/name_u] makes me think of coffee or the Beatles song. [name_m]Maximus[/name_m] feels a bit like Gladiator. [name_m]Maximilian[/name_m] hits that sweet spot. So cute.
We’re using [name_u]Maxwell[/name_u], though I love [name_u]Max[/name_u] on its own! I think [name_m]Maximilian[/name_m] is totally wearable, just depends on your personal style.
I voted for [name_u]Maxwell[/name_u] but I like [name_m]Maximillian[/name_m] too.
[name_m]Just[/name_m] [name_u]Max[/name_u], or [name_u]Maxwell[/name_u].
What about [name_u]Maddox[/name_u]?
My favorite Max- name is Maxfield. It’s classy and a little more unusual, and really cool!
I personally love [name_m]Maximilian[/name_m] with [name_u]Maxwell[/name_u] as a close second.
[name_u]Maxwell[/name_u] is my favorite from your list. [name_f]My[/name_f] all time favorite though is [name_m]Magnus[/name_m].
I have a little cousin named just [name_u]Max[/name_u]!
I voted for [name_u]Maxwell[/name_u], but I admit it’s just because I really love the possibility for nn [name_m]Wells[/name_m]! 
Personally I prefer just [name_u]Max[/name_u], it feels quirky yet established and gives me a similar vibe to names such as [name_m]Oscar[/name_m] or [name_u]Henry[/name_u], but [name_m]Maximilian[/name_m] and [name_u]Maxwell[/name_u] are lovely as well!
I love [name_m]Maximilian[/name_m], [name_u]Maxwell[/name_u] and just [name_u]Max[/name_u], but my favorite is probably [name_m]Maxfield[/name_m].