Sure, I'd be interested, but I think the Chicago guys need to chime in here. Seems Ted has submerged, and doing a confluence in Chicagoland without him would be folly.
I pretty much single-handedly arranged a Milwaukee confluence three years ago, and it was a great time, but lightly attended. The two major collectors, Ted Staberow and Jeff Thomas, brought their huge fleets of Rick basses on Saturday. I think we had maybe 50 instruments and maybe a dozen attendees. The reality is that to book a conference room at a hotel costs money, but some of that could be mitigated by overnight room bookings. In the Milwaukee case, I don't think anyone but my wife and I overnighted.
Another thought is to possibly find a suitable space through one's local community center, church, school, or bank.
Author: "The Rickenbacker Electric Bass - 50 Years As Rock's Bottom"