Basically what station has the worst layout. I can think of some...
Viper (SFGAm)- Viper's station is just too big. Add that to no grouper and the station can become a real mess.
V2 (SFGAm)- V2 is another mess. For V2 a station wait is 15-20 mins because of it's horrible capacity. Add that to the fact that it is really loud with the train going through makes it a bad experience.
Iron Wolf- IW's was probably the worst. Instead of most stations where the queue comes in at the center of the station, some bozo decided to cram the queue in right where the front row is. The station was also really small so trying to get past the people waiting for front row was very difficult
Gemini- Now i had to problem with Gemini besides for the fact that they had the entire 3rd and 4th cars sealed off to make it "easier" for the ride ops. But unlike say American Eagle You board in the center of the station. I bet it doesn't take much for the lines to interlock and again you can barely get thorough
Riddler's Revenge- I haven't been to SFMM but i've seen pictures and in the station the line basically forms a zigzag. Turned to the right about 45 degrees.
So what about you.....