Hi Steve,
I too recently purchased a Comanche, but I've owned a lot of aircraft over the last 40 years. Here's my tips.
Sam's Club has a heavy duty degreaser (It's purple and comes in a gallon jug) that when properly diluted and used in a spray bottle, works very well for cleaning the belly and wheel wells. Just spray it on and wait a few seconds and wipe it down with a soft rag.
I've used Meguiar's products for years and have found them to work very well. I also have a couple of Corvettes that I show and use their products on them. My current aircraft looked pretty rough when I bought them, but I knew they would clean up. I started with a good wash down using Dawn dish soap. This will remove old wax and leave a workable surface. Grease areas take some work using the product above. I then use Meguiar's clay bar system which will leave a nice smooth surface ready to wax. If you still have roughness then I suggest one of the DuPont buffing compounds and one of those orbital polishers you can but cheap at Harbor Freight. Once you have a smooth surface (that's important) wax it with any of the good quality products out there. I haven't found that aircraft particular products work any better than automotive ones, but I'm sure someone will take exception to that.
I live in Alabama and the bugs are bad about impaling themselves on the leading edges and windshield here. Once again I use a product by Meguiar's used for detailing. It comes in a spray bottle and works well for removing bugs. I normally use it at the end of every flight before they rigor.
Lastly, use care with the Plexiglas. I use a glass cleaner recommended for use with window film. That and one of these new soft towels works fine. BTW, I've had great luck with plastic replacements parts through Plane Plastics.
Here's some links:
http://meguiarsdirect.com/index.asphttp://www.planeplastics.com/indexGood Luck,
David Miller