I finally settled on 3072 x 768 resolution. Very little differences with the cockpit width, can't change cockpit height, and the icons are close enough to read
The big resolutions just make the icons so tiny as might as well go reduced option.
It takes a little getting used to huge horizontal views, but still have a ceiling over your head, but you do. Dealing with the monitor frames is no big deal either, especially if you don't usually fly with tear-drop canopy planes.
Setting up with a Nvidia card is easy, but their video capture doesn't work at those resolutions.