Here you will find periodically updated research and applied role-playing game information for optimizing RPGs to have the greatest change of enjoyment and immersion scores.
Optimizing the rpg experience, research and techniques for optimal rpg sessions:
Future version: (centralized research repository): https://catalog.rpgresearch.com (<pending, not yet ready for public use>)
Latest publicly accessible version (multiple pages): https://w3.rpgresearch.com/research/archives/public/rpg-research/rpg-optimization
Oldest version (one large page): (last updated 2014): https://www2.rpgresearch.com/blog/rpg-optimization-1