Mike,
I guess the "quiet occupied rooms" was a pretty popular request with a lot of people. Echo Collective made their library recently, and simultaneously some members here on Audible Worlds and I all wanted recordings of the same exact thing.
Echo Collective have their Quiet Spaces library posted here... http://echocollectivefields.com/quiet-spaces/
You're correct about the Sound Collectors' Club. There is an annual fee of roughly $30 (after conversion from pounds). I think it's worth it, but you're right in saying that it may not be for hobbyists/enthusiasts since you do have to pay for the yearly membership.
I'm still down to do the "quiet occupied rooms" on here if that's what everyone else decides they want to do. I'd personally really love to have more forest recordings though since quiet forests can be hard to come by. A lot of them here in northern CA (for example) are too close to highways and/or roads and aren't as usable because of all the cars in the background.
IRs were a close 2nd place for me -- seems like I don't ever have enough of those or forests.
Eric