Try to find a recumbent to try out. It may be better or it may not.
I also think others might be on to something when they talk about saddle height... could it be that your saddle height and crank length are working to put your hips into a range of motion they are not comfortable with?
I am 6'5" and have bought a few 180mm and 185mm cranksets, but the bike I am most comfortable cranking out the miles has a 170mm crankset.