Maybe I would try switching between bar 1 and 2 on the toon that got the proc : /swapactionbar 1 2

That way I would have 2 dps macro I would have to push all the time and one button per toon to swith bar

action bar 1 :
* button 1 = wrath macro
* button 2 = empty

action bar 2 :
* button 1 = empty
* button 2 = star fire macro

Jamba proc to follow these procs and know when an action bar change is required.

Not tested at all