(i recently sent this in a email... and figured others would like to see it...)

you should also try to remove the concept of your 'main' from your head. there is no main... just the currently active one and your alts. don't get mentally tied to any one character (unless its a tank)... when the active dies, you will need to be able to switch over as fast as possible to continue the fight, or they are all dead.

this is where pip comes in. you have 2 things to set up. one in keyclone and the other in wow. in keyclone, set your pip hotkeys for each region (i'll assume f8-f12 for discussion... just never use shift/alt/ctrl with these keys.. in the heat of battle, fumbling a key is very likely). then, in wow, set up 5 macros in each wow (25 total)... they would set your focus and follow.
ie:
/focus joe
/follow focus

that would be a single macro, and you would have it on ALL your wows... and you would associate it with f8, being your first wow.
next:
/focus sam
/follow focus

sam is your 2nd wow... and set that to f9. repeat for all your wows... for a total of 25 macros on the exact same 5 keys as your pip swap.

if you do it right... and joe is in the main region... and gets killed... you hit f9 and joe will swap with sam.. and all your remaining alts will now be focused on sam and following him. this allows you to click on a new target with sam and fire.. with your alts following his direction.

i hope that makes sense. if not, just drop me a note.