For Swill Pitz, Roach Motel and Shadow Cave it is an Advantage to be 55/56 cuz of ur gear and dps.
But it is not nice to boot. Thats true. I would do locked games and invite buddys. Open Games are for everyone in range.
But on the other side is that some low lvl leave game shortly before Fever ?! ( last run 4 left shortly before )
Not nice!