Really, the only potential problem would be the two different colors, and that’s really not that big a deal.  
Well, and ‘attracted to other mares’, but come on, by fan-content the Mane 6 are not just attracted to mares, but are usually in a relationship with at least two other Elements, creating a complex web of attraction.
 
This is a fairly reasonable character, written lazily, with a single visual quirk to make them stand out; The eyes.  
Why is it tagged ‘Donut Steel’ alongside OCs that look like they got rejected partway through a Rainbow Factory ‘processing’, with three or four clashing colors and bits of metal sticking out of them?  
Are they stealing it from someone? If the art isn’t actually original, I could see it, the same way I’ll accept ‘Donut Steel’ labels on people recoloring official ponies, but if it’s an original character I think people are over-reacting about the heterochromia.  
EDIT: Well, I did miss the ‘captain’ bit. Remove THAT and it’s a reasonable place to start a character.

gende-female
 
age-mare
 
yep mare is a age

Recolor = instant downvote

ORIGINAL THE CHARACTER
 
do not steal!

Yes Cantalot. Small town at the Horseshoe Bay. It’s the twin town of Canterlot.

CANTALOT?  
CAN’TALOT?!  
CAN’T ALOT!!!!