It'd be really cool to have some sort of checkbox on your collection that'd show on the pinball map that indicated basically, you're open to having people come play your 'private' collection. I know many people who are more than happy to open their doors to fellow hobbyists on request, and also many who wouldn't, so this would make it really easy to make it clear "hey, drop me a line, come on over and play sometime" to locals or people passing through, help foster some more pinball community, etc