Having only been told about it, it seems to me like there's a problem in the first place with that Steve showing up back in this timeline instead of growing old in the one he went to.
But you can stretch it by saying he grew old in the other timeline then came back with his suit in this timeline just to give away an extra shield he picked up somehow. That's a big stretch, but it's the only way it works out.
The other Steve is in the other timeline, his own, and he did everything fine. And he probably heard about Bucky sooner. Maybe even Hydra because why the hell not if original Steve can plan it out well.

Other time Thanos I think it's the main problem, there's a timeline now where there are no Thanos nor his army, so the events from Guardians of the Galaxy onwards are changed.

The movie did state that changing the past, doesn't affect their current timeline, right? iirc Hulk said so.

-I wish that photo of Rudd, Evans and RDJ didn't leak so we wouldn't know too much about the time travelling stuff. I also feel like not returning the stones to where they found them would have paved the way for more stories.
-It feels like Valkyrie and the other Asgardians who escaped from the Statesman all survived the snap. So did the Zehoberei (Gamora's race) and all the other planets Thanos has destroyed not get affected either?

I'm pretty sure someone between the Russos or Feige or whoever mentioned in an interview several months ago that the Asgardians lost half their people to Thanos in the ship, and THEN lost another half of the remaining people in the snap. They straight up said that Thanos is a liar / delusional / lying to himself or whatever their phrasing was. The Asgardians you see are the leftovers. That ship they escaped in was pretty big.
On Gamora, people have been remembering that the screen in the prison in the first GotG movie said she was the "last survivor of her race", and concluding that either that was retconed, or Thanos didn't give a shit if the remaining half of her people actually were able to survive or not, and it turns out they didn't. But the point really is that Thanos is an unreliable narrator. I think that's exactly why he's the Mad Titan, he's supposed to be a bad guy, you're not supposed to think mayyyyyybe he's a little bit right. His way doesn't work.

and hopefully, now that Iron Man is dead, if/when that stuff breaks means that Spider-Man won't be able to rebuild it and will just have to make due with just a basic costume and webshooters.