Basically been using 30 grams during and 30 grams pwo. It's made a huge difference in my performance the past 4 weeks, but I'm afraid it'll lose it magic soon. I stay around 7% body fat, so would staying in single digit bf range help maintain insulin sensitivity or what else can I do
Workout. That should keep you sensitive enough to the hormones you need. There's no need to add extra unless you have a medical condition.
Some say take Glucose disposal agents but triglycerides are more likely to be stored as bodyfat. So...idk why. Especially if they workout with sufficient intensity.
However...taking a GDA on days of indulgence can help. Personally...they give me hypo symptoms.
I used to be 385 lbs + so...if I don't need gdas...you probably don't.
Not to say don't experiment.
If you truely do maintain 7% and have for 4 weeks then stop over thinking fat gain and carbs. They don't make you fat. Nor does insulin in a normal healthy person. Quite the opposite in active people.