Suggesting [name_m]Hugo[/name_m], [name_m]Julian[/name_m] and [name_m]Emil[/name_m] [name_f][/name_f]- even though I think [name_m]Sebastian[/name_m] is the perfect addition to your sibset.
[name_f][/name_f]Of your list I would pick [name_m]Sebastian[/name_m] because if gives you the nickname [name_m]Bastien[/name_m] should you want to go with that.
[name_f][/name_f][name_m]Sebastian[/name_m] [name_m]Emil[/name_m] or [name_m]Sebastian[/name_m] [name_m]Hugo[/name_m] are such handsome first/middle combos.