Names for Female Sisters

Hello Everyone! I am hoping for assistance translating two female names (sisters) into Quenya. I am toying with the idea of twin sisters with names in that sweet spot of similar, just not too similar.

The first name, intended to mean "daughter of starlight", I believe comes out as Ilmariel.

The second name, "daughter of moonlight", seems to be Isilmiel. I think this is correct, but in looking at alternate choices I thought of going for "maiden of moonlight" which seems to be Isilmwen. The "mw" in the name seems a bit off to me. Since Quenya doesn't mutate like Sindarin, would leaving the "mw" be correct? Or is there a better/alternate way to construct this name?

As a related side question, I read through previous discussions on the site for help (such as this one: www.elfdict.com) and noticed name formations such as Calwen(dë). Do the parentheses in the translation simply denote the dropped dë from -wendë to show how the name is formed? Or do they suggest these dropped letters are sometimes retained in a name, making Calwendë an unusual but "correct" name?

Thank you for your help!

The name Isilmien would work for maiden of moonlight, as in Arien (day-maiden).

I believe (-wende) is the Quenya and (-wen) is the Sindarin, but I'm not sure.

Per Ambarkas' recommendation, Isilmien might work for the name of the second sister. Whereas Ilmarien would suit the first.

As for the name Calwen(dë), I believe the -dë is in parenthesis to denote the longer form of the name, whereas Calwen would be the shorter (perhaps diminutive) version. This can also be seen in the name *Alcarinquë* ("Glorious"), which is also simply called *Alcarin*.