Soooo back to what I posted earlier, what is the mission for the plane? If you are willing to put up with the hassle of trying to get stuff out of the back without a baggage door it will save weight. I have seen a lot of posts with people wanting to put one on a covered plane, never seen a post on how to take one out!! Just saying. If you have the 3rd seat mod you can use the tabs to clip in carabiners, same with the back seat depending on seatbelt. I have swaged cable loops (very light) in my overhead for top attachments. Depending on how the rear seat cover sets you can also clip into the crossbar in the front. I usually run out of cubic space before weight really becomes an issue with my cub, that is with extended baggage and a belly pod, winter flying is worse. For light extended baggage Carbon Concepts makes a very slick slide in one, check the pictures on the web page.
Everyone wants a lite cub!! But, once you add full fuel, gear and pilot they are no longer light. Once you hit 1700-1800 lbs do you really notice 20 lbs one way or the other? If you want performance at any weight add a big wing.
DENNY