We were there April 25-May 2 and saw Wishes 3 nights from the "Open viewing area". Except that only the left half (of the "open viewing" side) was open all 3 times. They had rope/tape blocking half of it. The first night (Tuesday, April 25) there were about 10 people in the right half of the area, but they all had really fancy camera equipment so I assumed they had set it up with Disney or they were Disney trying to get good video/stills without taking prime real estate during the last couple of nights when the crowds would be terrible. The 2nd time we saw it (Friday, April 28), there was the tape again. This time several groups of high schoolers from Canada were in the roped off area. I again assumed this was part of some package deal they got from Disney. The last night (Monday, May 1st) we were there, the rope was there and there were people on the other side of it, but it wasn't obvious what sort of group (if any) they were. I'm not sure if you could go around and just enter from the other side or if it was roped off for a reason. We were at the very end of a long week with a preschooler and a baby so we didn't try to find out.
That said, we were able to find seating for 4 adults, 2 preschoolers, and a baby about 25 minutes to show time the first 2 times. The last time we went and sat about 45 minutes early just because we were tired and coming straight from DHS. We also got lucky, and all 3 nights, everyone in that area stayed seated. It meant we could watch with the kids in our laps and not have to hold them up.