I think a really powerful move to make in the sea of game launchers is to add customizable controller profiles for games. As far as I know, Steam is the only other platform that does this, so that could help put galaxy a cut above the rest.

I would even just like to be able to navigate the launcher with a controller. Steam's controller support is screwed up for steam link with Microsoft store games, and being able to use GoG 2.0 with a controller would let me get around that.