Having taken some time to understand how you have approached custom scores, I can see that it will be easier to maintain “playback-only” tracks in Dorico than in Finale. I have done that in Finale, but there really is no concept of different versions of score layouts. In Finale, you can hide staves in the score, but that is a rather tedious process. It is much more straightforward in Dorico, as one can simply have a full score and a custom score, with the custom score being the one the conductor would receive.
Another issue that results from the Finale staff styles approach is that the music obscured by slashes, one-bar repeats or whatever still continue to take up space as far as layout is concerned. IMHO, that is just wrong, leading to hours of fiddling to get any sensible layout.
I still think (and you have indicated your preference as well) that slashes and repeats should have the ability to overlay notes as the ultimate goal. Those notes should be processed for playback, but should be ignored for layout purposes, as they are not visible. In the meantime, I do think it is a manageable solution to maintain two versions of the track (one for playback and one for score and printed parts.)