I now shoot at #61 (maxed).

If you are shooting it 30 times until fatigue at #70, and limbs usually go 40-50, 50-60, and 60-70,
I don't know why you should go all the way down to 40-50 limbs. Get a fast 50-60 bow and you
should be in business. My bow shoots flat out to about 24 yards.