When it comes to more endurances, especially including the 24h ones that PD mentioned shortly after launch, I'd love to see a mix of ones that pay tribute to endurances from older games like the Grand Valley 300km as well as real ones like the LM24, but I'd also like to see new endurances altogether.
One idea I had was a PP-limited event at Le Mans, specifically the layout without the chicanes, featuring historic sports prototypes that don't go into any particular group. I'm referring to racers like the Porsche 917K and the Ford Mark IV, even if they didn't necessarily race against each other in real life. Or perhaps even if they didn't race at all, like the Jaguar XJ13. Then again, it may be better to have more "inclusive" regulations that'd potentially include more than just four cars at most. But that's where PD-created liveries for the AI could be especially useful, as being limited to four models didn't prevent the Super Formula events from existing, no?