St Petersburg immigration is a mess. Terrible design - down escalators into a concrete holding pen, with no set queues, lines, or anything else (at least when we went). When we arrived (obviously after at least one or two other planes), we could barely get down and injuries were barely avoided when people couldn't clear the escalator due to the press of people. We also got shoved aside by German nuns.
Interesting place, but this part of the airport needs to be demolished and rethought from scratch.