Hey Shabby,
I like it when two people come up with similar ideas... I guess it means we're really onto something.
Check out the way I do it here... albeit about a year after your original creation. When I first saw this post today, I thought it was new... I think it is funny that I came up with a similar idea later without ever seeing this post.
Mine are backed with a felt lining that slips over the railings. I have made several for coaches here in Ohio and I have a few more in the works.
Also, watch for Ken Tamashiro's board coming in a few weeks to a month. It will feature many of the ideas you guys touched on in this thread, including the folding and expandable player trays. Maybe Ken will post some of the design drawings if he feels like sharing...