You have the opposite problem as me. I am parasympathetic dominant by default. I chill out, verging on apathy. What works for me, iron-clad, is more protein and fat and slightly less carb (maybe 30% of calories as carbs). The opposite, high carb (65%+ of calories), could be your fix.
How long after eating do you feel hungry again? Are you the type to forget a meal, and thrive on lighter foods? I think about food all day until I eat something ultra satiating, like steak fried in coconut oil and garlic, with whole milk (for example).
I too am parasympathetic dominant by default, any little thing that relaxes me plummets my metabolism. My basal metabolism is so low that I have to be under constant stress in order to function at all. I have actually been trying to raise adrenaline/cortisol for a while because I think having those stress hormones is better than being nonfunctional but I'm scared I'm starting to burn out so I'm trying to shift from cortisol to thyroid.
I do agree that low fat and high carb would be good for me but I try to do that already.
I used to get hungry pretty quickly but after prolonged PUFA avoidance, acclimation to coffee, and taking vitamin D, I can go almost 24 hours without getting hypoglycemic symptoms. Pretty happy about that.