I let each scene have access to the stack so it could say "manager.Push(newScene);" then the manager would call "OnPause()" on the old scene, then "OnEnter()" and "OnResume()" on the new scene also "OnPause; OnLeave();" when a scene is popped from the stack
Hahaha for some reason Steam just forgot my Dota client was there.... When it started downloading again I canceled then selected "Update" and it finished in like 2 seconds (it had to redownload the exe which it deleted for some reason)
Loading scenes, as long as the player knows the game hasn't frozen, anything's game. Art, bar, circular loader, animated or not, tips, lore, basic screen Overlaid on top of an existing scene or as a separate thing, no right or wrong way imo
witcher 3 got really fancy with their loading screens. instead of a progress bar they have a narrator recap the story of whatever main quest you're on, complete with an animation representing what is being said.
in-game, since it's forever one scene, I just show a black sprite over the whole screen, and use a white line to load across the bottom, there's like 10 steps to the loading and it's always super quick