Regarding deaths breath, I amassed a few hundred in preparation for 2.3 just by doing T6 rifts and looting whenever several elites die at once in the same screen, which happened a few times per rift; sure it slowed things down, but in spite of the cube I still have 300 or so on each character which is plenty. There's also a goblin that drops several DB's, I make sure to always loot that goblin.

For my setup I also use a DXnothing window with all 4 characters shown. I also have a few overlays (like the minimaps and mana bars; which for me I just take a rectangle out of the center of the globe as a source and line them up in a little rectangle. I do the same thing for health. I have miniaturized buff bar viewer's above the actual buff bar, those aren't as useful. I lately added a viewer for the pet/companion area too, also of questionable usefulness.

Being able to gauge all 4 characters health and mana at a single glance is absolutely invaluable though; and the minimaps make catching legendaries pretty reliable. I don't run with sound though.