I recently started working with the Jamba macro functions. Basically I made all of my macros like this:

"/assist #master#
/cast #damagespell#".

Then each of my toons has a button, that's not hot keyed. This button does

"/jamba-team set master <toonname> all
/jamba-macro use macros variables all"

So if I need to use another character as the master for whatever reason, all I have to do is change windows and click the "make me master" button. This rebuilds all my macros, and creates my new master as the main assist.

The only problem with this set up is it can't be changed while in combat.
I haven't gotten too deep into it, and the team I started it with is only level 13ish right now. But it seems to work ok for my needs.