In Wiggins you have a super athletic slasher who can drop 20 every night, and showed really well on the defensive end in his time with the Warriors. Is he overpaid? Sure. But just because he's overpaid does not mean he isn't a good player and valuable to the Warriors. He plays a critical position and he has versatility to his game. If you were to trade Wiggins for Bradley Beal or Joel Embiid, you end up with a big hole at the 3 spot and huge defensive issues. Being able to maintain the cross matchups at the 1 & 2 spots with Steph & Klay is so important to the effectiveness of this team.
The one guy (besides Giannis, who is a pipe dream IMO) who would fit is Ben Simmons. He can handle, create, finish in the paint, and defend all over the floor. The fit with Draymond could be complicated, but I think it could be sorted out. Simmons would cause teams all sorts of problems if he were surrounded by Steph & Klay.
The truth is that I don't think any of these blockbuster deals is very likely to get done, so I've focused more on potential smaller deals that creates more depth and a more complete roster.