I watched it 4 times from 3 different locations on my last trip:
#1: walked into the hub (on the right near the Tomorrowland bridge) a couple of mins before the show started. It was hot, it was crowded. Very good view though. We stood behind a man in a wheelchair and that helped. We were also on the part where the path sloped so that also helped.
#2: Watched from the Transportation & Ticket Centre. First time there so I was a bit confused as to where to stand. Turns out it is right where the ferry unloads. I walked in through the ferry exit gate and stood off to the side. Nice view, low key, fantastic music. But lights are not dimmed. And of course, no projections.
#3: Watched from the fence behind the fountain (in Robo's map - between "All Guests Open Viewing" and "The Hub"). We got a spot directly facing the fountain. It was wonderful - watched it from here 2x. Nobody standing in front of us (which I worried about in the fenced in grass viewing area) and plenty of cool breezes. The fountain was calming and added a lovely element. Very clear view of the Castle projections. Even better was a comfy seat on the ledge (great place for littles to stand during the show too). To the right and left of us the view is blocked by shrubs so people don't pack in tightly on either side.
Edit to add location #4.
#4: My brother and SIL went back for one final viewing. This time they went right up to the stage. He reported: "It gave more detail but lost the wider story coz of the angle. I enjoyed the experience immensely though thanks to the nearness - so it's still a great experience. The nearness means you can't see the big fireworks behind the castle".
My SIL'S comments: ""Well, since you have tried your most preferred spot at the Walt & Mickey statue,the spot we were at in front of the stage could be a nice new experience as you could see the projection on castle more clearly in details. The fireworks on both sides are bigger and brighter, may be overwhelming but in a nice way. Those fireworks from behind could still be seen though slightly hidden because of our closeness to castle. Nothing short of magical, I promise!"
My brother wonders if the Mickey statue would be better. That used to be my favourite spot but it is more tightly packed and there is no comfy ledge to sit on compared to Spot #3.
My daughter just commented that she prefers the Mickey statue spot in the Hub (we have watched Wishes from there multiple times). I think we'd like to try in front of the stage and that is not very crowded.