Most monitors are designed for near field application so it's most important they be placed in proper relation to the engineers ears. There are under speaker isolators that will reduce interaction between the workstation and the speakers.
You have three walls that the workstation can go against. Since the room is almost square it won't make a lot of difference which one you use. You can use room correction or EQ to reduce bass peaks and room treatments to control reflections.
If you add a subwoofer then you will have deeper and better controlled bass.