as kosta noted, we already mix horizontal and vertical views with the Sample Editor and the Automation as well. so from those examples it becomes apparent this is not such a big issue as most people seem to think.
also, i think if you’re gonna go for vertical Audio Tracks, you have to at least give some thought to the idea of collapsible channel tracks as well. this is gonna become a big issue if people are planning on crowding the Pattern Editor with audiotracks. some people are gonna wanna hide those things.