I like
Mellan though I haven't seen nor heard of it before.
It has a very soft sound and look. This may on the other hand be its weak point. It is very close to
Melanie - and yes, melon. I would use it as the middle name only, if I was you.
Combo suggestions:
Angus MellanHenry MellanClancy MellanMellan ConnorMellan EnnisFergus MellanFinbar MellanFinlay MellanMellan FinnMellan KilianLucas MellanOscar MellanMellan QuinnThomas Mellan