For what you're planning on using her for, temperment is by far and away the most important quality, so if she's sweet and easy to handle, you have what you need.
Two things jump out at me about her. One, she's extremely short coupled - her middle section is signifigantly shorter than her hindquarters or front end. That's not a great quality for dressage/eventing or hunters or jumpers, but it is a more desirable quality for a Western horse doing ranch work.
Two, her hind leg is extremely straight from hip to hock, with very little angle to her stifle. This means she won't have as much "push" or "engine" from behind, and will also have trouble really "sitting" or rocking back on her haunches. Certainly won't keep her from doing what you want her to do, but something to be aware of. Horses with this conformation do much better if kept fit, and gradually introducing hill work under saddle when she's ready is the best way to build the muscle she needs.