Re: Downey's last?
I think the end of IM3, if that scene is accurate, will be a setup for A2. GotG will take place before all the other PII movies. Think the RDJ cameos will get a bit tiresome if they keep shoe horning the character down our throat. Not like he had to show up in CA:TFA or Thor. They may want to get Stark a role in a PIII movie, since IM4 is probably off the table. Never say never, but I don't see it happening. Maybe in the next Hulk or Ant-Man movie.