Agreed, you can get 1/2 oz glass on a large roll,
http://thayercraft.com/104.htm and WB poly from the box stores. There is also the EZE Coat poly that doesnt warp balsa since it is thicker then the WB poly.
http://www.deluxematerials.com/products_building.html Its real easy to use and seals the wood well. A couple coats of sanding primer/filler, wet sand smooth and paint with your choice of colors and it will look great. I have done mine this way, and it is looking pretty good, ready to paint, just have to find the time to do it, but should probably cover the rudder and elevators with cloth and attach them first so the paint is even.
If you go the monojoke route, you have to sand it or paint wont stick to it, and may not stick even after sanding.