I don't see anything that screams "breed me" but there isn't anything terrible about her either. I don't think her age or the changes to her joints would prohibit breeding. Doc O Lena was foundered so bad she could barely walk and she had two foals. You might have heard of them Dry Doc and Smart Little Lena!
I'm kind of the opinion that there are a lot of horses to choose from right now and it would be much cheaper and faster to find one you liked and buy it rather than trying to raise one yourself. It takes much less time and you get to pick the color and the gender.