Two servos in the bottom wing only should be fine.

I moved the landing gear foward by 1/2 inch and have had no problems with nosing over on a grass field. Just be sure to hold up elevator when starting to taxi.

My Hog has a Saito .91 and balanced perfectly without adding weight. The battery is in the forward compartment under the fuel tank and the receiver is in the main compartment just behind the battery. Your Saito 1.00 should weigh about the same, so I doubt that you will need to add weight. With a cowl you may find that the battery and receiver will need to be placed further aft.

I needed to add down thrust and right thrust to the engine mount to improve flight characteristics. Of course, your mileage may vary.