It's not that kind of power. Or at least, it isn't until he gets all the infinity stones, maybe. Generally, he's been really good at raising armies, punching things, and executing people. He has a pattern. He plays to pattern even when he doesn't strictly need to kill someone. Yeah, maybe his beliefs started him down this path, but he is clearly unwilling to re-examine them. I mean, he is definitely an evil villain, even if he does have a historical reason for how he got here.
I agree that Strange's plan will foreshadow how they beat him. Which means it centers on Tony. After all, Strange's plan set things up so they were able to trade for Tony's life. That's the thing he accomplished, so it has to include the way to defeat him.
Thanos's glove is DEFINITELY damaged. Heavily so.
The next three movies are all apparently set prior to Infinity War in what appears to be the largest diversion so far from chronological filmmaking in the MCU. Ant-Man and Wasp is immediately post civil war, Spidey is immediately following the previous spidey film, and Cap marvel is 90s era. This appears to be intentional so they don't have to deal with the deaths at all until Endgame.
Overall, was pretty good, saw it twice, and I agree that they definitely framed it around Thanos as the protagonist, which is kinda fun. I don't particularly empathize with him, but I like seeing the villain as the central character, and anyways, there's plenty of sympathy with the heroes to hold up that end of things. It's a decent sort of glue to make a cast this ridiculous work. Also...dear god I feel bad for the visual effects folks.