I'll be honest, I've got a hybrid system going on right now. I still use /assist focus in my macros, saving space, but also have a method to switch windows easily.

In Keyclone, I have F8-12 set for my PiP's (or whatever it's called) F8 is my main, through f12, my lower right. In WoW, I have 5 keybinds set (I use the upperkeys on the right right sidebar) those keys are set as F8-12 as well. The frist one is:
Code:
 /target Main
/focus target
Then on down the line so that every toon has an F# cooresponding to their PiP window. When I hit F11, everyone targets and focuses the toon from that window and Keyclone switches them out for me so that everyone is focused on my main window, regardless of which toon it is.

You'll have to update the macros if you swap party members, and for each team, but I haven't run into any macro space issues yet. You can also tune the macro for other things, like a shift modifier or ctrl to heal that toon.

Hope that helps.