Jessie Inchauspe [1] created a business (she's the "glucose goddess") and wrote books around the different blood sugar responses she and others have to meals, exercise, etc... I don't recall all the ideas, but here are the two I remember: Exercise before and/or after eating smooths out the blood sugar response to food. When eating a meal, it's better to eat high-fiber stuff first, then complex carbs, then protein, then fats, and eat simple carbs last (Or something like that order).
GLUT-4 activation in the muscles primes them to take up glucose and other nutrients. So air squats or going for a walk before/after a meal can significantly blunt the insulin response, because there's less glucose in your blood stream, because more of it has been ported into muscles.
Yeah, I think so, though my recollection is that a baked potato's glycemic index is kinda high. For more authoritative list of details, you could listen to the following podcast with Inchauspé: https://overcast.fm/+AA4G32XuwoA
[1] https://en.wikipedia.org/wiki/Jessie_Inchauspé