The new maneuvers few like not planned additions, but ways to differentiate the new ships. A-Wing and TIE Interceptor area extremely maneuverable ships and don't have S-loops and T-rolls...
Because those maneuvers weren't designed yet. The Core Set involved designing all the maneuvers they thought they'd need: I would be surprised if they considered not having the K-turn. S-loop and T-roll were made for Waves 6 and 7.5 respectively, where they had a lot more information. If they thought they were a good idea in Wave 0, they'd probably be in there.
The choice is either to add new maneuvers when you think they're appropriate, or to stick to your starting set of maneuvers. The choice FFG had with the Segnor was to give the new ships the Segnor or to not implement the Segnor at all. They can't go back and Segnor all the old ships.
I never proposed fully interchangeable pilots, in the first place, just a little more flexibility for a very few characters.
Then why add all the effort of separating the cards when only a few pilots are actually interchangable?
If only a few pilots can jump ship then you might as well just release pilot cards for those pilots in those ships. Want a TIE defender Maarek? Release a Maarek card in a TIE defender. Doing it this way lets you adjust the pilot ability or pilot skill to balance if you want to and saves you having to design pilot abilities for ships you haven't designed yet.
And that's what FFG does.
