re: No more large crews for ISS
Depending on how many people a CEV will be able to carry, it seems obvious that this vehicle will be able to effectively service the ISS, along with unmanned cargo vehicles, either Progress or ATV. I don't see any real problems with running the ISS long into the future.
Until then, I have been unable to figure out why simply parking another Soyuz somewhere on the ISS wouldn't double the rescue capacity required, but then nobody asked me.