I actually don't think Thanos is going to be in this at all. We'll see though. Here's mine:
POST CREDITS 1:
INT. WASHINGTON- SMALL MEETING WITH JOINT CHIEFS AND TONY STARK
Sec. of Defense: Well, Mr. Stark, do you have anything to say for yourself?
Stark: I beg your pardon, Mr. Secretary?
Sec. of Defense: We damn near had a global crisis on our hands that would've cost countless lives and it all derived from Stark Industries' technology that went horribly out of control. Out of YOUR control. So, I repeat, do you have anything to say for yourself?
Stark: Oh, I'm sorry. I could've sworn this was the "Hey, Avengers, thank you for saving the day" party. I was kind of curious about the severe lack of pinot noir and---
Sec. of Defense: This is not a joke, Stark!
Stark: You're right, it' not a joke. We DID save the day. My team and I...saved the day. I don't think it would be asking too much to, for once, show a little gratitude.
Sec of. Defense: And yet this crisis would have never happened in the first place if you and your so called "Avengers" were on a tight leash and held accountable for your actions. That was our mistake letting you all roam free and leaving us to clean up your messes. Well, no more.
Stark: No more?
Sec. of Defense: We're introducing a new initiative, Mr Stark, that you are going to spearhead---
Stark: Geez, what is with you people and initiatives--?
Sec. of Defense: It's time for you, all of you, to get in line. Once and for all. The question now is....Whose side are you on?
End shot of Tony looking worried and indecisive.
POST CREDITS 2:
We see Ulysses KLAW in a jail cell in an unknown location. A mysterious figure approaches him.
Mysterious figure: Uylsses Klaw. How very nice to see you up close and personal.
Klaw: Eh? Do I know you?
Mysterious Figure: No, you do not. But I know you. You are notorious where I am from.
Klaw: Heh, so what do you want?
Mysterious Figure: You ran into conflict with a group of Americans that were... extraordinary.
Klaw: Yeah, those freaks are the ones who put me here.
(We reveal the figure to be T'challa and he's dressed in full Wakandan garb)
T'challa: I would like to learn more about them.