Here's a way to avoid the long lines that are usually found at the Riv in the afternoon and early evening. If you aren't a players' club member, you should be... no cost.

If you have a host, remember to go to the Host area to the right of the Coffee Shop entrance for checkin. You get to sit down there [g]. There used to be a "Platinum Players" lounge for checkin of higher level players but it had been closed the last time I stayed there.