My opinion, and that's all it is, is that hotfoot is metatarsalgia. Moving cleats back helps because that reduces pressure on the metatarsals. IME hotfoot has nothing to do with cleat size or shoe stiffness. I've seen LD riders with it who had all the "right" equipment. That said, some shoes and insoles make the metatarsals more comfortable than other shoes and insoles do.
Especially on long rides, I make a point of trying to pedal with my heel cups, not my forefoot, and relaxing my ankles. My wife needs her cleats moved all the way back and her shoes fairly loose or she gets foot cramps, though not hotfoot. Everyone's different. I think it's possible that many bike shoes simply have too narrow a toe box, though that does make a more stylish shoe.
Don't set your saddle height by some formula and then use a pedal stroke which works with that height. Rather develop a pedal stroke which is easy on your feet and calves and set your saddle height for that stroke, by feel. Within 4mm of heel-on-pedal, knee locked, usually works.
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