Any vegetable oil will work for the mites, thinner oils may need a layer of petrolium jelly or a&d ointment over them to keep them there. I use castor oil for that reason, it's very thick and stays pretty well. I would still go with neosporin on the raw areas until healed so that you don't have any infection set in, and try to keep the feet as clean as you can while those areas heal up. The build up of gunk on the legs and feet from the mites over time, as you found out, is very, very hard and can cut off circulation.
It's not uncommon for toe loss in severe cases. Time will tell with the other toe, depends on how damaged it is. Some of the nails do look a bit long and she'd probably be more comfortable with them trimmed, just be careful not to cut too short and into the quick, just trim a little at a time. With some time and care she should recover and be fine, maybe with a couple of shorter toes. Chickens lose toes to frostbite also, same thing happens and they generally get along fine.