There is alot of info on this plane here, it's a very popular plane, and for good reason. When I built mine, I lightened the wing by replacing spruce spars, with balso, and lamintated carbon fiber strips on top between the spar/sheeting. I ran the strips out about 2/3 the span of each half. Also enlarged the lightening holes that are already presenit in the fusalage by about 1/4" or so. Then of course a good dose of sandpaper all the way around getting every bit of non-wanted mass. Did the rudder too, enlarged by about 2" I think, and elev's about 3/4", it reallly has a more asthetically pleasing look this way also I think.
BME 50 for power...not cheap mind you, but it's really the only way I would go if I built another....no less then the 50 anyways...and it does have plenty of power to leap out of a hover nearly. It does take a bit of finesse though, as from my observatioin, with that much power you can easily tear one of these up. Don't get me wrong though, the kit does build very strong, but when you take the lighter approach precaution must be taken. I' really think though that the wing with c/f in it is much stronger with less flex, and just the weight of the wood difference was almost 1/2lb. Each spruce spar by my scale said it weighed between 3 and 4oz's, and the balsa weighed less then 1oz. That is x4 remember, so it all adds up. I think a c/f spiinner, and c/f gear would make quite a diff also. That kind of stuff isn't cheap though.. . Mine is going strong though, and I'm looking at a good year of flying ahead. Good luck, and keep us posted on progress.