One problem I had with many gang videos as a viewer was when the Lers would be making so much noise simultaneously, you couldn't hear the Lee. Whether all were trying to tease at the same time or a lot of times, even laughing louder and harder than the Lee. Sometimes there would be an eruption in laughter from banter but you couldn't hear what was said that was so entertaining in the moment. And as Soles_Scream said, sometimes the Lees then try and be the one going hardest.
Gang tickling has a visual appeal in art or photo. If it had to occur, I think one or two on each side of upperbody and one for feet and lower body suffices.
And the Lers have to realize that even when skilled, they have to be more like the male in a M/F vanilla porn scene. The Lee is point of interest visually and verbally. ;-)
Of all gang tickle video material (and I qualify 'gang' as 3 or more Lers), I personally thought TA's "Non-Stop" and "Stretch" gang series were the most enjoyable. (again, just my opinion). The Lers all understood the mission (especially since all the Lers had to take a turn as the Lee). The intensity was consistent and focused without being out to "torture", the Lers were very good at not blocking the scene, they weren't more vocal than necessary, allowing the Lee's reactions to shine, they didn't compete to be the one getting the biggest reactions.