firstly, make sure your husbandry is on point. one hot hide w/ a UTH, one cold hide, thermostats/hygrometers to measure temps and humidity. Personally speaking- you want a hot spot of about 90-95, ambient temp of about 80-82 on the hot side and about 72-75 on the cold. again, these numbers are a personal preference based on what my danger noodle perfers and thrives at.
as far as FEEDING goes: my suggestion would be first starting to feed him LARGE ADULT mice. get a bigger, more sustainable meal in him and the hunting and pacing around the tank should start to subside. my friend has a female BP who still to this day will not eat rats, but she is happy and healthy eating an adult mouse once a week. work on getting bigger meals in him, then try and get him from a large mouse to a similar sized rat. they smell different to the snake, so trying to make them look and seem similar as prey should help.
ALSO make sure you weigh him EMPTY (aka after he urates/poops and before you feed again) it's kind of hard to say an average weight, but I'd say a healthy +3ft male should be EASILY 700g.... my female is about 3ft 8in and she weighs 982g just to give kind of an idea.
keep us posted!