RE: shrike 10
I'm in a similar situation, have the shrike 10, but I'm going to use a K&B 3.5 cc rear exhaust with tuned pipe. I've probably read every shrike thread while researching. The most important thing I've read is to keep it light. I plan to install mini servos rather than standard. This will save an ounce or two. I also plan to use a 6-700 mah nimh battery pack rather than the standard nicd pack. And finally, I bought a light weight receiver rather than standard size. This will save quite a bit of weight. For me, the investment in lighter radio equipment is worthwhile because almost all of my planes are in the .15-.25 size.
Some people have tried installing landing gear. The consensus appears to be that it was not worth it.
Can't help you on prop selection, I don't have a Norvel.