I love Felix and I don’t see it as too basic with Benjamin or any name really.
How about:
Rafe / Ralph
Conrad
Rufus
Ronan
Reggie
Pippin
Atlas
Hartley
Orson
Zephyr
Ryker
Oisin
Jarlath
Lorcan
Wilbur
Ashby (not best flow to Benjamin)
Kit (do you have one already? I know you have an Iv0, Sash@, An0uk & Jun0, nothing that order).
Heath
Lief
Nils
Sky
Cyan
Rome
Auden (maybe not best with B)