15lbs with a g-62 thats good, I built 2 one at 17lbs with a q-52 and one at 18.5lbs with a g-62. The 17lb plane wouldn't snap out at low speed at all. I sold it before I could get the c.g. just right and never flew the second, sold it first time at the field. Anyhow, if you are that light do you mean that at low throttle it snaps in level flight or when you pull elevator or etc...IF the elevator isn't to sensitive and you are not climbing while inverted you could go back a little further on the c.g.. This would get the the plane flying with a slightly lower angle of attack and keep the wing from stalling. If this is your first big airplane it may seem to be flying faster then it is.
Good Luck
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