Re: Should "Star Trek IV" have introduced a different NCC-1701-A?
It goes beyond just some doors -- there's several lines of dialogue in the movie ("Half the doors won't open," "The ship's in pieces"), plus Scotty having just "fixed [that damn thing]" (the Red Alert notification-system), the turbolifts messing up, and the transporters being completely down, which pretty much point to a massive systemic failure of some form aboard the Enterprise.
Some of that could be just off-hand exaggeration by a few crewmembers to drive home their main point that the Enterprise
-A isn't quite up to par yet.
"Don't sweat the small stuff--it makes you small-minded..."