how can i make my esc run cooler

run a higher turn motor and that ESC can handle a 5s pack...high voltage + low KV = cooler system but Feigaos will run on the hotside it the way they are designed. Good thing they are cheap and make sure your ESC timing is set at 0. You can try a Medusa motor they are better than a Feigao but not as good as a Neu.

5s with 10XL should be a decent system