For PVE I currently have
/cast [@focus]polymorph

This is fine when you have time to setup raid markers and focus on each mob; you can't go too fast because it doesn't register the newly selected mob. In PVP I think this would suck

Now I was thinking of modifying the macro to:

/cast [@focus]polymorph
/cast [@randomtarget]polymorph

I'm yet to test if the second polymorph will fire if I have no focus?

Is this the best way to handle PVP polymorphing? I've never bothered before now.