Hmmm, well, this is one of those movies where you have to again take into account what it was in competition with at the time.
http://en.wikipedia.org/wiki/Peter_Pan_and_the_Pirates
From 1990 to 1991 Fox had launched their own Peter Pan cartoon show which was pretty popular at the time, and was known for having a very Hook-centric set up where he and the pirates were given as much screen time and focus as Peter Pan and company, not to mention being made considerably more formidable seeming than the impression you'd get from some of the other versions of Pere Pan that came along before them. This version of Captain Hook was voiced by none other than Tim Curry, who is himself kind of a big deal when it comes to memorable, over the top performances.
In short "Hook" seemed to largely get upstaged, while it's true that "Hook" saw planning going back as far as the 1980s or before, the youth of the time and nostalgia seeking parents for that particular 15 minutes had their own image of what this should be like, minus the goofy baggage of a middle aged Robin Williams being Peter Pan.
This is similar to other points I've brought up before, like with why "Alien 3" got trashed as badly as it did (comics which were well known at the time to franchise fans did it better).
That said, it is very true that "Hook" is not a bad movie, it did what it set out to do well, and it had lavish production values. It just had the misfortune of being a comedic sequel to a not-so serious story that came out in exactly the 15 minutes where the 1990s has birthed it's own version of Peter Pan which has replaced the Disney version "Hook" was largely leaning on in people's minds.
That said, I think Oz, Wonderland, Never Never Land and the like have oftentimes suffered from being prisoners of their own material. There is a lot that could be done with this sort of surrealistic fantasy, based largely on how people decades ago thought a child's mind might work, but for the most part I don't think most writers really want to take it in the right directions, and oftentimes it turns into little more than an exercise for writers and actors to re-interpet characters and put their own stamp on them, and that becomes the focus more than anything. Sort of like how Tim Burton's Oz pretty much turned into Johnny Depp and Helena Botham Carter trying to one up each other in terms of quirkiness at the expense of the storyline.... but that's just my thoughts.
I echo the whole "I'm not sure if this needs defending" thing myself, after all this movie staying around, being re-released on DVD and Blu-Ray, and the whole nine yards speaks volumes. Defending it against the critics of yesterday is kind of pointless when the environment is so different. You can't see things the way they did right now, as what is arguably a not-very-well remembered Cartoon wouldn't hold up the way it did at the time.