John,
I love all of the bells & whistles as much as anybody, but I purposely decided against loading down the plane with every available toy. No panel mount radio or transponder, just a handheld Icom & a portable GPS. I can go pretty much anywhere I want with those 2 items. Not as nice as a panel mount, but I will still get there.
No carpet or upholstry, just the Kitfox supplied seats. Carpet just collects dirt anyway. Had rather have nice varnished wood floorboards. Old school I guess.
No redundancy with instruments, etc. The Grand Rapids EIS has more features than I will ever use & if it stops working, I'm confident that I can manage to keep the engine running without it. If you have ever flown Champs or Cubs, you know what I mean. No need for dual electrical busses & batteries, etc. I have the basics for VFR day flight. No lights, so when the sun goes down, I will park the plane.
The items I just listed will easily add more pounds than you would think possible. Their addition can certainly add to the enjoyment of flying and at some point I will add some "extras". But for now I will be satisfied with the basics & enjoy the added bonus of a great performing aircraft.
I also followed the Poly Fiber manual closely. I used Poly Tone for the final color coat and didn't go overboard in adding extra layers of paint & sealing materials. High gloss fabric looks good, but I'm sure the end product will weigh more. And I think the Poly Tone finish looks "right" on a fabric airplane anyway.
So, no magic here in the building process. Just have to remember that there is always a tradeoff for every item you add. And I'm sure as time goes by, my airframe will pick up some weight with added toys. But I'm confident that I can add the toys that I want and still have an airframe that will come in under 800 lbs. That still leaves over 500 lbs useful load with a 1320 gross. I can live with that and be VERY happy.
Certainly not knocking the Rotax, but I think I proved that you can build a light Kitfox with a Continental 0-200 engine without trying too hard.
Danny