Furazone ointment comes to mind. Learn what conditions lead to foot problems, and just how long it takes you to bootie up. If there is some doubt, quickly ointment all their feet, and put on older booties. If a stronger ointment is required, the dogs needs to be laid off for a bit.
Swollen feet are much worse than they appear.
Learn to know the exact size of each dog's feet, and how warm they feel in various temperature and trail conditions. If they seem too big, or too hot, you have a problem. Lay them all off for a bit. If you are a Sprinter, the same advice works, except for the accelerated healing. Also, watch for broken toes and sore shoulders on hard stuff.