You’re actually taking a substantial performance hit by undocking your panels to external windows. The game’s UI is badly optimized.
Undock a few windows and my FPS can drop from 60 into the 30s, even if they’re just simple text panels. Folks say they can’t tell the difference above 16 fps since that’s what the old timey silent films on the hand crank projectors are displayed in. But man, as soon as you turn your head quickly to the left to see if you’re abeam the numbers when in the pattern, the smoothness of 60 fps vs the chop of an erratic 30 something fps is night and day.