Another thing that came to mind (and this is something I’ve noticed in other programs as well) is that the default spacing algorithms would benefit from some tweaking where the priority of space between manuals and the pedal relative to the grand staff is concerned. Dorico’s default behavior when it is trying to fill a page is to leave large gaps between the manuals and the pedal part, rather than a.) slightly increasing the spacing of the grand staff (which allows more space for the counterpoint that is so common to organ music) or b.) simply allowing more space between the systems. (B or a combination of A&B is preferable.) I’m guessing that Dorico treats the pedal part like a different “instrument” rather than an integral part of the overall grand staff system.
Out of curiosity I decided to check a few of my various organ editions. I checked scores that were almost 100 years old and a few major current publishers, including urtext editions. In every case, the pedal part is either the same distance from the grand staff as the grand staff is wide (ie- 11mm between both hands and 11mm to the pedal part) or more commonly, the grand staff is wider relative to the distance of the pedal part (ie- 12mm grand staff and 9-10mm to the pedal system). I’m attaching a screen shot of Dorico’s default behavior and a bit of Henle urtext of a piece by Liszt. The Henle is in perfect keeping with every other edition I looked at (about 8).