At the 2001 15 m Nationals in Uvalde, we used a finish line and had 69 gliders in the contest. I think this meets the criteria of lots of gliders and limited runway space.

I don't recall any problems recovering 69 gliders on the runway and taxiway with the line finish. Everyone was told to land long and clear the runway.. Crews were waiting at the mid-field taxiway and pulled their pilots out of the way. We crew-less pilots made sure we rolled well clear while we retrieved the car.

You don't need to simulate this, we have lots of experience with it, you just have to go back a bunch of years.

As has been said before in this thread, all it requires is discipline and organization on the part of the pilots, the organizers and the crews.

The finish line is by far my preferred finish gate. A 500 ft cylinder with speed points all the way to a rolling finish is my next favoured finish.

The concept of navigating to some point in 3D space at the edge of a cylinder with a floor for a finish requires too much head in the cockpit at the wrong time. With a line or 500 ft cylinder to the ground, the final glide can be accomplished visually within the last 5 miles and keeps the heads out of the cockpit.