Joe, most important for a scale completion beginner is have a experienced spotter. He/she can talk to the pilot and calm him down. The pilot can concentrate on the airplane and his maneuvers.
maneuvers: have a plan and stick to it. Don't change on the competition day.

My rule for engine selection is different. Before I put any dead weight in the airplane I increase the engine size. There is no substitude for engine displacement. You can fly your maneuvers even at half throttle with authority. Besides that it make it possible - if desired - a scale size (or close to ) propeller.

Here is a 1/5 P-47D 2RA with a Torch 90cc and a 25 inch four blade propeller....now we talking scale. The propeller will be not judjed - but the overall realism adds up[img]../../punymce/plugins/emoticons/img/trans.gif[/img]