I've seen Alicorn OC's ALL OVER the brony section of the internet. AND IT BUGS THE HECK OUT OF ME.
[insert awesome intro here]
Ok, so, let me discuss this more thoroughly. If our OC is an Alicorn, that means they are,
1. A leader of something,
2.A worshipped godlike creature.
3.And basically IMMORTAL.
If an OC is an Alicorn, you have to be a leader. Therefore, you would have to make it a leader of some area. But, if any random place in Equestria has it's own leader, it just doesn't make sense. Unles sof course, you have something about that in your headcanon. And a leader has to have some important role in that area of Equestria.For Example, Celestia and Luna raising the sun and the moon. If your character is an Alicorn, it is indeed a godlike creature to ponies, and therefore is a leader and is worshipped. If your character is a leader, then they don't have TIME for whatever they do, whether it be analyzing, ranting, or whatever. If you are an Alicorn, you are basically IMMORTAL. Un;ess your OC has an elaborate backstory, Having an Alicorn OC make no sense WHATSOEVER. Considering all us analyzers are all human, this doesn't have much sense in an OC being immortal. This also starts off my new topic. Mary Sues.
Most people make their Alicorn OC's Mary Sues. If you don't know what that means, a Mary Sue is, it's a perfect character or as close to a perfect character as you can get. They are overpowered. Nothing can defeat them. They are perfect in every way. Everyone loves them. They have no flaws.
I HATE MARY SUES.
(Clears throat awkwardly) Sorry 'bout that. Okay, so, your OC has to have a well thought out backstory for it to make sense. It doesn't have to fit in with the MLP canon, but ultimately choosing the Alicorn species just because you want to both fly and have magic, just can't fit into any canon or headcanon.
And remember, If everyone's Super, No one will be.
So to wrap up, don't make an Alicorn OC unless you have a very elaborate backstory that fits into canon or headcanon. And I suggest using Alicorn OCs for fanfictions only.