IMO, paint is a giant pita! Gelcoat is easy to apply, easy to sand and repair. Despite lots of advice to the contrary I use a roller and lots of wet sandpaper, no tools at all. Just do a little experimentation with the hardener so that you get adequate "pot life". Roll on two or three coats in succession, just like spray painting. I use a waxed product and let it stand over night before sanding the next day and have had no problem with amine blush (or what ever that gooey stuff is). If you have heavy orange peel, start sanding with 240, if not you can start with 320, graduate to finer grades as the spirit moves you. I use wet/dry sandpaper, a bucket of water and old towel, to keep the dust down and the work surface clean. You can control orange peel by thinning with a little styrene.

You can certainly use any tool you like, I just find them too noisy and I'm in no big hurry. Changing paper often makes the job much faster than you might think, whether working by hand or with a machine. Sandpaper is not the place to economize.

As for the surface crazing, you're on your on. I'd just sand 'til I got tired and start gelcoating.

If your supplier can't explain the advantages between waxed and unwaxed products, it would be best to find one that can <img src="http://www.catsailor.com/forums/images/graemlins/wink.gif" alt="" />.