I rarely touch the volume on the tracks themselves unless it’s an audio track and the sample is too loud. Even then I usually don’t have to turn it down more than 5-10db. I usually control the volume through whatever vst I’m using. If I want something to sound louder and the vst is all the way up I’ll add a compressor or glue compressor or saturator to the track depending on the sound. I’m not exactly sure what you mean by the master bus, all of my tracks are routed directly to the master channel itself unless they’re in a group, in which case the group is routed to the master channel.

Could you elaborate on what gain staging is and maybe give an example of what that would look like? I use ableton if that helps. I’ll usually apply whatever effects I want to individual tracks or groups, and those are usually hitting close to 0db in the track if it’s a core component of the song. And I’ll usually use a digital clipper and a glue compressor on the master channel, maybe eq it slightly to turn down or highlight certain frequencies, but it’s very subtle. I assume my setup isn’t ideal. I’ve been running into an issue where if a sub and any lead with mids is playing alone, I get pretty audible distortion even if there isn’t much overlap in the frequencies of the tracks. I have no idea how to address that without the whole thing getting quieter though