Totally Lyra

Your secret's safe.  I certainly hope enough time flying would help with a fear of heights.

You mentioned you'd like to have magic, so why not try to hide your wings rather than your horn? I'm sure an alicorn would be powerful enough to cast an invisibility spell on them or something. (or take the example of a certain little black filly and wear a vest )

Yeah sure, I’d like to have magic, but disguising myself as a pegasus is better from a tactical point of view. If I hide my horn, then people won’t know that I can do magic. This can be really useful in certain situations, like if u were facing Chrysalis for example. She wouldn’t feel threatened by a Pegasus. That gives u the element of surprise, giving you an opportunity to unleash a magical attack at her when she is not expecting it.

I would probably take it in turn to disguise my wings or horn. That would allow me to experience both magic and flight without attracting ponies’ attention all the time.

How about choose changeling then? That way you can sometimes have wings and sometimes have a horn, depending on which you want at the time. You can also choose a different appearance for either form so no one will wonder why you're sometimes a unicorn and sometimes a pegasus. Sure you don't have the all around power of an alicorn, but you can disguise what you are a lot better.