With big bro’s name, I think either [name_m]Max[/name_m] or [name_m]Jude[/name_m] is the choice. Have you considered [name_m]Tristan[/name_m]? I think it goes lovely!
As far as longerish middles, maybe:
For Max(well): [name_m]Halloran[/name_m], [name_m]Jameson[/name_m], [name_m]Tavian[/name_m], [name_m]Oliver[/name_m]
For [name_m]Jude[/name_m]: [name_m]Amias[/name_m], [name_m]Nathaniel[/name_m], [name_m]Merrick[/name_m], [name_m]Tavian[/name_m], [name_m]Elias[/name_m]
Hopefully these help! 