I like
Reina as a name, the Spanish word for queen. It's pronounced the same way, "RAY-nuh."
But rain with a random "-a" on the end does nothing for me, sorry.
The attraction of a name for me is usually the associations they bring to mind.
Reina makes me think of the Spanish court through history. Loads of interesting angles to the name. But "rain + a" gets me nowhere.
Lavender is don't care for as a name. How about
Lavinia?
Maren is OK.
Skye brings to mind the gorgeous Scottish isle of the same name.
Love it.
Calista is beautiful (literally), but I prefer the double "L" spelling because that's how it is in the original Greek script. Shine? That's a verb to me, not a name.
Love Zola, by the way.