From what can be gauged from that sole pic, it appears she likely has pretty good feet. It is clear that her heels, quarters & bars are quite overgrown and heels appear a bit forward of where they should be though. It appears that the the right side(in pic) heel *may* be slightly lower, indicating possible lateral imbalance, either due to farriery or the way she carries herself. If for eg it was an abscess that caused the bulge, she may have carried her weight on the other side for relief, so the outside heel grew longer since the last trim. Sorry I can't be any more definite or specific than that, but hope you appreciate that a couple of pics don't give an accurate enough idea. I didn't mean you necessarily had to have the bulge pictured in different angles, but different views of the entire hoof would give better ideas about balance probs, etc.
Re the cracks, unless you lived in a desert, I wouldn't suspect just dryness being an issue at all, especially over winter. Horses/hooves have evolved for semi arid environs and their hooves are meant to be dry on the outside. Painting stuff on the outside can be a culprit, as these preparations frequently make matters worse(although they can make the feet look prettier). There is moisture in the inner wall, but as the tubules migrate out, they lose their nuclii and dry up. This superficial cracking/shelliness is generally related to the nutrition of the hoof. That's also not just about diet, but if the feet are not functioning well for some reason, there will be less circulation to nourish the cells. So it's possible her back feet don't show this because they're generally functioning better(backs often tend to be better, for a variety of reasons)