I think its a pretty average average. I visited Lahore this weekend in my 7 year old SE Saloon. Average speed was 140 (got ticket as well). From F10 Islamabad to Cantt Lahore and back to F10 Islamabd, it costed me 3000 worth of Super.
Had I follwed your mentioned speed limit and a high octane-super mixture, I assume my average could have improved big time.