River is one of those names that I wouldn't use for my own child, but I think soudns pretty neat on someone else's child. I have a real affinity to water bodies, so I think
River has a somewhat mystical, ethereal sound to it. Because of that association, I'm going to say that I like
River Gaia the best out of the combos you've listed. And also because the combo two of the elements: water and earth. You need a combo that has something to do with fire and air to go with it. ;)
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