Since you are at the balancing stage what is the total weight of the plane when balanced ?
The predicted weight of the ARF is 6.5-7.5 lbs and the kit's predicted weight is 7.5 lbs, I have found that the predicted weight is optomistic at best and at worst a cruel joke.
If the all up weight when balanced is 8 lbs or less I think you are in very good shape and if it is less than 8.5 lbs you are still ok.
Of course you already know that the heavier it is the faster the airspeed will be to keep it in the air.