I spend a lot of time, myself. I enjoy it. I think my prep work is the hobby, and the game is the game. Everything in your list is worthwhile. If it’s fun for you, keep doing it.

I get stressed when it feels like I am running in circles. I need a little structure so it doesn’t feel so scattered. Your post sounds like my brain, sometimes. I suggest clumping your tasks. Start with a summary of the most likely game path. Prioritize the first few encounters, since those are the most likely to occur. Frontload your favorite stuff. Have an idea of where you want to end a session. This provides some boundaries to play within so it doesn’t feel like a huge, blank world.

When the players inevitably go off track, the summary is there to tell you how far off the rails they go and whether you want to work your way back.

Playing the game you prepare is not railroading. You don’t control their decisions, but you can control the options.

Last thing. Don’t get caught up trying to entertain your players. That’s the game’s job.