The OC I made was the first thing I had ever made in the pony creator, and so I dont plan to use that for my OC picture any more. (If i can change it) NeverPony drew my OC after that, which is a very well-drawn project that appealed to me. I will definitely use that.
I'd probably re-make fireblood in the pony creator. I'd remove the accessories, that was basically a test. I'm not exactly sure.
Fireblood is mainly an omnipotent character and quite versatile, but I had no intention what so ever to make her a "Mary Sue" as you said. I just think alicorns are cool, and yes I did mess up on the mare's head. I'll be sure to fix that.