First off, Elora is stunning. I don't think she'll undergo any difficulties living with the name Elora. I think I marginally prefer the name Eliora, since it has clear Hebrew roots and in my opinion that's always a cool thing. Ellie can be a cute nickname for Eliora or Elora.
I completely appreciate Nesta but I think the flow of the combination is a little off. Ideally I don't think the middle name should end in -a if the first name does, but that's just my opinion. As far as I'm aware, Nesta is the Welsh version of Agnes, which does not mean peace. It means purity, which is lovely anyway.
You said that you appreciate musical refrences in your name choice. Lucky for you, the Choir of Saint John's Elora is one of the best choirs I've ever heard, so there's your reference.
As for a cool boys name, what do you think of Elias? It seems really handsome to me and it seems like the logical alternative to Elora. If it's a girl, go with Elora, and if it's a boy, go with Elias. : )