Speaking as a huge Iron Man fan, Tony should get as much screen time as Anthony Hopkins in the first Thor movie. Suit up get a fight scene in there maybe in the middle or at the end (taking on robots of flying drones or something) while Spider-Man defeats the main villain.
People complaining about RDJ in this forget that other movies in the past have had relative unknowns in these movies with big established actors surrounding them.
For the last time, this isn't going to turn into an Iron Man movie. Just like the Avengers and Civil War movies weren't Iron Man movies.
The constant complaining gets me less and less excited about this movie.