[name_f]Vasilisa[/name_f], the way that you’ve described the prn, evokes too much vasoline. Does this name have history? I think I’m familiar with Vasila or [name_f]Vasilia[/name_f], like Basila or [name_f]Basilia[/name_f], [name_m]Vasil[/name_m]/[name_m]Basil[/name_m] for boys, but this one seems a stretch. It seems Greek or maybe Russian, because of the history of the name. With a strict prn of that nature, Vah-see-lee-sah, it’s pretty, although heavily exotic/ethnic.
[name_f]Juliette[/name_f] is pretty and has enough classicness to ground it well.
[name_f]Arianwen[/name_f] is out there, but lovely and approachable because of [name_f]Aria[/name_f] gaining some popularity.
[name_f]Rosalie[/name_f] is lovely, its star has been rising with Twilight and might fall a bit, I still think it’s a lovely name and the [name_f]Rose[/name_f] part will always ground it.
[name_f]Evanna[/name_f]…I like the idea of it, and it fits certain trends, but it also just evokes [name_f]Vanna[/name_f] and [name_f]Ivana[/name_f] for me, which are less pleasing than the name itself. I’d far prefer [name_f]Eva[/name_f].
I’d use/consider [name_f]Juliette[/name_f], [name_f]Rosalie[/name_f], and [name_f]Arianwen[/name_f]. [name_f]Arianwen[/name_f] is NMS more than the other two but it still really appeals, so consider that a good sign. I do think [name_f]Arianwen[/name_f], like [name_f]Vasilisa[/name_f], stands out from most of your taste. [name_f]Juliette[/name_f] and [name_f]Rosalie[/name_f] are natural sisters, for example, and while [name_f]Evanna[/name_f] wouldn’t really fit in with them, it would work enough. [name_f]Arianwen[/name_f] and [name_f]Evanna[/name_f] is actually an OK pairing to me, because they both have a Welsh connection.
What middles to put with them really depends on your taste and last name, if [name_f]Vasilisa[/name_f] is meaningful to you I think it pairs OK with [name_f]Juliette[/name_f] or [name_f]Rosalie[/name_f] up front.