The chance there will be newtonian physics is non-existant if you ask me.
I am programming a little space strategy sim with nVidia PhysX myself, although I haven't been working on it in almost half a year. Anyway, I decided that I would use newtonian/realistic physics only for projectiles, rockets, guided missiles - basically everything except ships. The problems that arise with realistic physics in regard of manual ship control as well as ship AI for performing even the simplest tasks were too hard for me to tackle. Instead I gave them friction (only for linear, not angular velocity), so they wouldn't really need to worry about dealing with inertia and could basically just steer in their desired direction at all times. I mean, if you just want to reach a certain point as quickly as possible, that's easy, no matter what's your inertia. But if you want to keep formation, fly maneouvres at close range etc., it gets complicated. And then there is always the question how to deal with maximum velocity. Logically, you should be able to accelerate indefinitely. But that means it also takes forever to come to a halt or redirect your heading. Pretty complicated... sure it's possible, but it contradicts the approach that egosoft is taking with Rebirth.
For trading I also used to have one or two AI controlled transports, but I did move them manually and check prices for the sectors they were in, while trying to capture pirate ships myself. But I doubt that you can do even that in Rebirth. It's just a notion, but there is probably a reason with the underlying game mechanics why you can't have cargo anymore. Why would there be a restriction like this otherwise - only to annoy people? I don't know what that reason could be, but I'm starting to believe that trading might be even more simplified yet.
