Beginner DSLR camera Nikon vs Sony

You've done a lot of research on the web. You seem to know about the SLT low light handicap. Now you are hoping experts are able to assist you further. I think, that if you haven't already, you need to handle both cameras. Which ever camera feels like an extension of you and meets your standards is the camera you should choose.

I am a Nikon owner. Despite that, I am not very happy with their video implementation. In video mode, focusing is slow, so it cannot keep up. There is also no aperture control in video mode. I can only imagine that Sony is better, as I have no experience with their cameras ( DSLR' s).

Both  companies have good to great lenses. Sony uses Carl Zeiss for some of their better lenses ( or at least the name). Nikon has been making optical glass since the 1920's.

In  summary, the system you choose must meet your needs and feel comfortable using it.