Admittedly I haven't been using a multiple monitor setup since I bought a 43" LG 4k screen. 1.5x scaling is no longer an issue though, as of the latest version

Admittedly I haven't been using a multiple monitor setup since I bought a 43" LG 4k screen. 1.5x scaling is no longer an issue though, as of the latest versions of gnome and wayland, that just works and I haven't noticed any problems with scaling at all (still requires the "tweaks" app because gnome can't be arsed to expose any power-user features in their settings ui).