probably tennis because those judges get a seat lol. thought i wouldnt enjoy having to voice a call on the microphone
bball or football i currently have the most knowledge on so those would be the most plausible
its been a decade since i refereed soccer games on a nightly basis.
MMA would be fun too, id choose that for sure (but only if PRIDE rules! =P)
boxing not so much, those guys are harsh and hit refs both by accident and deliberately also lol