Clebby, it is a good idea to start with a kit first to get your hands around the building process, but if yo uwant to start with a scratch body then go for it!
if you are talking about curves as in rounded corners, you can use a router for that, or do what I am doing and file it away if you want your own custom curve.
Adding a top requires a lot more skill than just routing a body, best to leave the high end maples until later on. If you were to do it I would use the same template for the top as well, make sure your body and top thicknesses are good enough for the playability, dont make it too thick.