Jason I feel your pain, as I experienced plantar warts in 1973 and had them excised in outpatient surgery!!! Will never have surgery again unless I'm dying. ANyhoo, I don't know if my suggestion will help your painful and chronic calluses but just this year I've been experimenting with the miracle of comfrey poultices and salve. In fact, just this week my annual thumb problem of deep, painful cracks at the outer corners of the nails, which usually took a couple weeks of slathering vaseline and lotions on them, I just resolved in two days by applying comfrey oil (made it myself with crushed leaves soaked in olive oil for several weeks. No pain, the dead skin is softening, and it's getting better instead of worse as usual. It's also softening the dry, alligator skin on the inside of the thumb nuckles where my tools rub constantly - much more effective than any lotions or balms.
You might want to do a little more research on comfrey but I think everybody should have a tin of it in their medicine cabinet. Soak your feet in epsom salts, then scrape them per others' instructions, and then give your feet a lengthy massage with comfrey every night when you take your boots off.