At the jam I was able to get play-tests going with both four and five players. It worked well with both numbers. I imagine it would also work well with more than five people, but I don’t expect it would be very interesting with fewer than four.
I’m happy with how the movement mechanic worked out. I wasn’t sure if players would have enough control over movement with the way the mechanic is set up, but it seemed good when we play-tested it, offering enough control to be able to manipulate people’s movement, without giving absolute control.