Of all the sanders I own, the RS2E required the biggest learning curve for me, even more so than the Rotex. It should settle down after breaking it in and you will probably notice a subtle difference each time you use it - the sander will seem to smooth out. You also need to move it back and forth quickly - much quicker than with an ETS or RO sander. I find I have to use both hands for the best results too - very slight downward pressure (and I mean very slight) to guide the sander forward and the same pressure on the back to guide it back. Sometimes I position my right hand on the back handle similar to a plane with my index and middle fingers on the side of the body and pointing forward. I also sometimes position these same fingers on top of the sander and keep my palm on the handle. I find this allows me to get the right amount of downward pressure to control the sander and keep it from wandering. I keep my left hand on the front knob at all times. You may need to adjust the vacuum slightly, but honestly the holes in the pad are pretty big and allow for good dust collection and air flow and I find that I can use the sander at full suction without issue. This has become my go-to sander for most things as I find I can move through my sanding regimen more quickly than with an ETS or Rotex sander for most things. It covers such a wide surface area that it is great and it keeps things flat. This sander is awesome and I would just spend a little more time with it to learn how to finesse it and to break it in adequately.
Good luck and let us know if you have any other questions.
Scot