I absolutely agree. But I feel ESB was handled better in it's technique. I love cliffhangers and genuine feelings of 'so what happens next' but this time just felt a little more on the frustrating side.
That in itself, yes was satisfying and like you pointed out, the end of the film does provide an answer to the opening dilemma of the film - Luke Skywalker has vanished. That's fine. It was more of the style that it was done that wasn't quite to my taste. Imagine ESB like this - Vader reveals he is Luke's father to him, he falls, the film then cuts to black and credits roll. In this scenario, yeah, we're given the same information, but it would be much more of an abrupt ending. Those 5 or 10 minutes after the reveal let the audience process the information and you're given a bit more of a farewell. Yes, it still does the 'wait for episode 6!' thing that I'm not a fan of, but it's more of the film-making style here that I'm taking issue with. Just maybe a short exchange between Luke and Rey would have gone down a bit better than a booming soundtrack over just a sad faced Luke looking at her. I dunno, I still loved the film, and I'll be over it when the next few films are out, I just don't think its a technique that the film industry should keep using going forward.