I have to finish up most of my merit badges and start my project--hopefully about 6 months away.
I like your project idea! No one in my troop's done something like that (it's all park benches and gardens). I think I'd do a better job with a video than a park bench.
I never made it to Eagle scout, but I was a Brotherhood member and chief of my OA Lodge (Aquehongian 112)
I had hoped to go back as an adult (I am 43 now), but I have some issues with the BSA currently since they do not allow known or suspected homosexuals or atheists, which (IMHO) goes against everything I believe the scouts are about. Not to mention that they discriminate while being subsidized by the federal government as a "patriotic organization". I didn't know that bigotry was patriotic. I realize that most people involved do not subscribe to those things, but the organization has officially stood by that doctrine.