I don't like
Narcissus, but I love the Catalan form, Narcís (nuhr-SEES), it's one of my favourite names and I could use it.
It's quite popular here, even if not really among children, because it's the patron saint of Girona, and I live near there.
Echo is nice, something fresh and different, but not really my style.
Both could be good middle names. I can't tell you if the association is too much, Narcís here is fairly "common", and people don't usually think about connotations.
Eva