THe is my mare she is 15.2. She has always been a "Hard" keeper when i was at a boarding facility and always had to pay more and she was still skinny! But as soon as I brought her home it was easy to feed her. She is registered AQHA/APHA. She is thoroughbred. She is dewormed a lot, worked a lot, and has tons of muscle so Im not sure if she is just buff or to fat? Opinion!!!
I too think she looks good for winter. I'd like to see her slicked out and more lean muscle, come spring /early summer.
I wasn't real clear on her breeding either. Assuming she's a QH, I'd say she looks in good winter condition. Maybe drop 50# or so come summer. I think a lot of good owners tend to keep their horses on the tubby side. ( I'm one of them so don't think I'm pickin' on ya! )
Be strong and courageous, and do the work. Don't be afraid or discouraged by the size of the task, for the Lord God, my God, is with you. He will not fail you or forsake you.