until you receive a more qualified answer, maybe the answers of this post I made bring you some light in some of your questions .
I’m quite sure GPU supports FP16 and INT8.
I’m quite sure DLAs only can run TensorTR models INT8 optimized
ISP,DLAs,7way VPU,x2 PCIe, make it quite different than jetson Nano even for camera support, I think you should look for AGX Xavier to get usable things.