You might be careful considering her as a broodmare. Pregnancy can often make a mare more susceptible to founder - particularly if she is prone to being overweight. And what mini is NOT prone to being a little chubby?
I have minis. The case as you have stated would not deter me from bringing the mare home AS LONG AS YOU HAVE BEEN UP FRONT WITH ME.
First time founder can be like a first heart attack - a wake up call. It sounds as if you handled it well, kept up a good program of rehabilitation, and followed up.
A horse like this, I would drive slowly and carefully at first, then add work appropriate for her. If she fitted up well, I would likely start dressage work, and likely even try her at combined driving. Most likely, she would be fine - particularly if ex-rays show no rotation.
I likely would not, however, breed her.