Technically we should optimize our system to reduce the loading time, and I know it's very expensive.
As a designer, I wanna help by figuring out ways to make players FEEL the loading time is shorter.
1. Animate the loading screen
eg. loading background, loading bar, or new animated element
--> Never make players feel the screen is frozen
--> Add something fun for players to look at
--> eg. ease in and ease out. Make the loading feels less buggy
"Fake" the loading animation a little bit if necessary.
--> Stuck at 90% feels less painful than stuck at 20%
for example, if your average loading time is 6 - 15s. You can "fake" the animation as:
it always take the app 1s to load from 0 to 50%, and 2s from 50% to 90%, then 20 s from 90% to 100%.
Whenever the actual loading progress exceeds the fake progress, take the real one.
3. Make sure the assets are cheap so they can fit into the bundle.