Is your feature request related to a problem? Please describe.
Just possible improvements include:
Toggle options for a various 'Introduction Sequence' option

X†) Pre rendered 3D multi-block diorama, maybe not as elaborate as Create can be, but a ritual, purple fire, spirit cutting down a tree (HAHAHA) and chefs kiss would be items falling into the stable-wormhole.

X†) Splash screen with a pre rendered image and text- FTBQuests

2. Follow the highlighted box and read the pages- Patchoulli

When the option is on it should have be up to the dev using Modonomicon to choose between:
Only show the introduction sequence once per installation
Show on the first use in any new world.
Show on first use when opening the game
Always show when opened.

Describe the solution you'd like
X† is an Either option in my opinion, either a splash screen or a diorama but don't do both. Method 2 is basic and boring but works.
It might seem excessive to show a splash or pre-render every time, but I think a clever mod dev could hide clues about their mod in plain sight.

Additional context
I know most player will hate the idea of a splash screen every time but I had a college professor that taught me 1 thing about film, everything they show you in a good film, they show you for a reason. It's why when you re-watch something you know to look for the clues, you're in on the 'secret.'