Can someone please explain how past!Thanos et al got to the present-day Avengers compound? I was in an emotional haze for the entire three hours so I probably just missed an explanation, but... that's a lot of tech for them to conveniently have, yes? Even if they got the coordinates from current!Nebula (which I think is what happened?) wouldn't they still need Pym particles and a time machine of some sort? It's not even regular time travel because they're coming from an alternate timeline, correct?
Also, out of the many questions (and rage headaches) I've had re: Steve's ending, there's one detail I'm not clear on that can probably be explained easily: when he went to the alternate timeline to be with Peggy, was that the alternate timeline he and Tony created by going back for the stone and particles? Or did he create another new alt timeline? Because if so, that's bugging me. A lot. He's essentially creating/cloning a familiar world knowing that alt!Bucky is currently captured and being tortured and Hydra is just being its usual horrific self. Even if he and Peggy and Bucky team up to take down Hydra and clean up history, that's still a lot of pain and unhappiness to knowingly start up again, and it's unlikely that they'll have a 100% success rate so there's a whole new timeline of people getting killed or hurt.
We know so few solid details about the infinity stones (in the movie universe, at least) that the writers could make just about anything possible. If they were determined to give Steve a sentimental ending with Peggy, I wish they had just handwaved something using one of the stones instead of mucking around with time travel again.