I've certainly heard the first, and I understand what they mean -- they don't want a dozen people milling about back and forth after the plane is empty and they're trying to count. But a large majority of the time people would be wanting to move forward -- if you just got up while the rest of the passengers are deplaning, and as you got to a row you want slide into it and stay put, I can't see how they would know or care, since they didn't know who was sitting where to begin with and they can't begin that through count until the rest are off, can they? Be conscious and polite about it (wait until there is a good gap, move in quickly and don't delay the people getting off when you restow, etc.

As to the last, I don't know current policies (it probably varies based on the planned and actual layover, staffing, gate layout, and more), but one of our favorite flights when the kids were little was a ~1 hour stop at MDW. The FAs were very friendly; the pilots invited my kids to come sit in the cockpit, and then we still had time for my son and I to deplane, pick up some food, and reboard before the regular boarding while my wife and daughter hung out on the plane. I don't think we moved seats (once we were settled in those days, that was that lol), but it made the next 4 hour segment quite pleasant too.

I like that WN accurately describes stops vs connections in the schedule -- a far cry from the fake same-flight-number "stops" like one I had recently on another airline, where it was scheduled the whole time as a "plane change" and involved going from one end of the concourse to the other. Yeah yeah I know why they do it, but there was no benefit to me in having it listed that way vs a normal connection. I've even seen WN delay new boarding and escort through passengers on first when a plane was taken out of service unexpectedly.