I think all three of those are good choices!
Some other suggestions I haven’t seen mentioned yet:
[name_m]Andrei[/name_m] / [name_m]Andrey[/name_m]
[name_m]Emilian[/name_m] / Emiliyan
[name_m]Nayden[/name_m]
[name_m]Orlin[/name_m]
[name_m]Yasen[/name_m]