A Dazzling Question

What type of ponies would the Dazzlings be? I mean, they have powerful magic, ish, so they could be unicorns, but they are shown as so many different types of ponies.
So, who do I think they are?

I believe that the Dazzlings are a mix of the pony types...
ADAGIO: unicorn
ARIA: I'm stumped on this one
SONATA: pegasus

I think that Adagio is a unicorn because it seems fitting to who she is. Even if she doesn't have siren powers, she may still have powerful magic and be able to cast spells.
Sonata's personality makes her seem like a pegasus. She is very energetic, and flying seems like it would second nature to her.
I'm stumped on Aria because she seems like she could be one of two pony types, an earth or a unicorn. I see her as a magical unicorn, but also as an earth pony. It is hard to explain, but I can imagine her as a pony both ways, thus making which way I like better hard to decide.

Tell me what pony types you see the dazzlings as, especially Aria, who is my favorite siren!