for me... i have set my focus and pip swap keys to be the same.
ie: bob, sam, joe

f8: /focus bob
f9: /focus sam
f10: /focus joe

that is the same on all characters. those keys are also my pip swap keys. hitting f9 will bring sam to the main area, etc

i also have '/follow focus' on the same key for all. sometimes i will add the '/follow focus' to the focus macros, but it can mess up casters.

after that, it's fairly simple. all my targeted spells are the same across all charcters:
ie:
/cast [target=focustarget] fireball

i just place the macros in the same slots... hit f8 at the beginning so all wows focus on my main (bob in this case)... and if bob dies, i hit f9 for sam... sam pip-swaps with bob and all remaining use sam as their focus. then i just click and fire normally.

it's been fairly simple for me. what am i missing?

(and yes, round robin hotstrings are in the next release)