Geoff, you are just plain greedy when it comes to eye relief.
I find the 19mm Pano has just about enough eye relief (1mm more would be good), and the 27mm has too much. I expect that for me the 24mm would be about right or a tad too much for the Panoptic eyecup design. With more ER you'd need an adjustable eyecup like on the Pentaxes (I wish the 27mm had one).