Re: Who's side are you on?
Ant-Man and Wasp are getting their own origin film right after A2, it doesn't make sense to have them in it and step on their own movie in the proces. Likewise with Doctor Strange. We know Black Panther really may be in it. Ms. Marvel...meh, after a certain point you're putting too many heroes in not to mention Ms. Marvel doesn't really solve the power punchy thing a whole lot.
The twins are the oldest Avengers sans the originals. So it makes complete sense that they should be in the sequel.