I applaud your simulation first approach. However, especially regarding sensors models and real-time performance in complex scenarios, the simulation technology you are using won't get you anywhere close to where you are trying to be. This will lead to false confidence, massive amounts of wasted time and money and safety issues as the scenarios get more complex. Far too much shadow and safety driving will still have to be used. L4 will still be unobtainable.

Here is an article on my POV in SAE's Autonomous Vehicle Engineering magazine. Notice Sebastien Loze, Simulation Lead for Epic Unreal, agrees with me. (He actually came from my world. CAE/Presagis). Unreal, Unity etc are great in the visual domain but no more.

SAE Autonomous Vehicle Engineering Magazine – Simulation’s Next Generation (featuring Dactle)

https://www.sae.org/news/2020/08/new-gen-av-simulation

I would be glad to go into the tech in detail.

Michael