I don't have much experience at this, as I've only just started.
Not really addressing the original question, but as for the part of interfering with the rest of the race, my thought is if you make the decision to step out and address the first car, finish that first and move on to the pile up around your foot.
The times I've marshalled we've had a tight track, so I try to cross the track and right the car in one go. I'd finish what I was doing, then turn to the poor sods car I just booted. It's maybe not the 'fairest' thing to do, but once I've committed to sorting a car I think it'd probably take more time to switch to the crash I've caused.
Difficult to please everyone, whether you decided to stay or go.
Still it can be daunting & stressful. I wonder if the marshal from the original post is on oOple.....
On a marginally off topic note, how many times do buggies with reverse catch you out ?
