Hunter 3, 4 or 5 hunters was my thought. They're top dps with a 1-button rotation anyway, right? Try to heal with HoTs?

I was also thinking about a way to shuffle through which window has focus manually, and then binding that next screen button to mouse wheel or similar. Such that you'd be mousewheeling to manually cycle which window has focus while spamming your regular attack buttons. A programable keyboard with a special button for "alt-tab" may work also - such that your attack sequence would always be a combination of 2 keys hit in rapid succession. (think: 121212 where that's actually doing alt-tab, /cast fireball, alt-tab, /cast fireball, etc)