I orginally mapped a macro called assistmain to my 'F' key since the orginal assist feature of 'F' was kinda lame. The general concept is:
/assist focus
/follow focus

Gets everyone to assist and follow. Not bad.
The next part I added was Jamaba to fix the follow part. It does a "follow after combat". So you almost never, ever have to push follow, since the alts auto-magically follow after getting out of combat. I still use my 'F' key since I want to drag my melee people around during combat.

The next part of /assisting, I have my alts focus my main and then put in target options so my spells go off no matter who I am targeting. General idea:
/cast [target=focus-target] DPSSpell
/cast [target=focus-target-target] HealSpell

I would love the idea of voice commands, but my guess is the technology is just too new. Imagine cell phones back in the 90's. Okay, but not amazing. I would give it like 10 years until it works without so much training and having to be exact.

I use my Logitech G15 keyboard for 90% of my boxing stuff. Extra keys that aren't in my way to do stuff for everyone. I use 3 90% of the time. Attack, heal, misc. I just put /castsequences for the 3 keys and that is all I pretty much use. The rest are for random stuff (mounting, accept all macro, send pets only, etc).

Hope that helps, and good luck.