ahh ok. I'm pretty sure theres no way to switch via a hotkey although it would be a nice new function for keyclone
But as far as positioning the rogue, you might want to search for a thread (forgot who posted it) that talks about 5 boxing melee classes. There was an idea of having, in your case, a rogue
following your main (tank?) to where you can line up the rogue like this:

(tank>)-(<mob)-(<rogue)

in this case the < shows which way they are facing. Also, they described having a follow macro only on the rogue which would make it come to a distanced caster:

(tank>)-(<mob)-----(rogue>)-(<caster)

this would be used to escape from AOE attacks.
all of this is explained clearer in the post, so you should definitely check it out.