They're decent names. I like
Caspian, but it's not something I would use myself.
Violet is also decent, but it seems very Hollywood trendy to me considering that
Violet is also the name of
Jennifer Garner and
Ben Affleck's daughter.
I prefer
Marlowe for a boy, but it's not bad as a middle name for a girl. It's close enough to
Margo that it doesn't strike me as extremely masculine sounding.