Even though you presumably did a factory reset of the watch already (in order to pair it with a new phone), try resetting again. I noticed the same problem with my watch, and the notifications came back after a reset.
Regarding the Remote Camera feature -- on the phone, open your camera, and then on the watch, swipe up -- do you see a prompt to open the Remote Camera feature?
Did the factory reset and the camera still didn't work. Then I noticed 'camera' as an app on my phone that I could download on the watch. Once that was installed Camera Remote now works.
I haven't tested incoming calls yet.