Three things in no particular order of impact to blood pressure:
1. "Loose seatbelt effect". The GUI sliding in and out when you change speed drives me crazy. Add that it makes parts of the GUI go off screen, and my gears are grinding.
2. I had three things, but I'm old, and can't remember #2.
3. Eye bleeding jaggies inside stations. I know, it's a combo of FD not really caring, and my low 5760x1080 resolution, but it really jumps out at me and stabs me in the brain stem every second I'm in the station.
These three things combined seriously detract from my desire to play the game. I still do though.
