I loved it
Many - really, really many - years ago I flew FfaM to Paris and back at least once a week, usually in a 727 or 737. I found sitting up front, RH aisle seat, where I could watch the cockpit activity thru the open door, was great, really instilled in me a sense of confidence in professional air crew which has never left me, even though it all takes place these days behind a (dark blue) locked door. On several occasions I was invited into the cockpit and yup, it was a thrill.
Flying with an open cockpit door in a commercial passenger aircraft is unlikely ever to become the norm again, but as an SLF I'm glad I was there, when it was.
RaF