A name that “goes” but doesn’t “match”

My son’s name is River. The ‘meaning’ I usually give when asked is that a river can be tranquil and deep, or wild and raging. It’s full of metaphors for life. I’ll be having a daughter next, and I want a name that has a similar depth, but I don’t want to be corny and name her something like “Ocean” or “Sky”.

Any suggestions? I’m not interested in gemstones, and gender neutral or ‘less girly’ is a plus but not a requirement. Other names under consideration are: Zelda Rumi Nix Deva