Will the jetways be accessible from inside the terminal into the aircraft too with the avatar?
That's not currently possible with P3D4 because, jetways are skinned, meaning their structure changes when they are docked so, what is normally used to have the Avatar standing on an elevated surface, the so called "platform" in SDK terms, doesn't "stretch" with the jetway animation, so the Avatar would fall off the jetway as soon as it moves.
However, it's possible to let the Avatar visit undocked static jetways and I guess we might to something to allow users to see a jetway in first-person mode even when it's docked or while it's docking, if we either "locked" the avatar in place (like a static observing point ), or if we placed a custom camera there.
There are still lots of new features we could likely add in P3D4 (only), because the camera API there is so much more powerful than the very limited one available on FSX.