I felt that way the first few times I watched it, but after 5 seasons you just learn to put them into completely different categories. They just took the concept and went in a different direction, so it's apples and oranges, really.
My only real problem with the show as it is now is that they seem to have forgotten about the reality show aspect. The characters still talk to the camera, but they do a lot of stuff (Michael trying to buy weed off the guy's at Vance Refrigeration, for example) that would get them into a lot of trouble; and in the first part of the last episode, the camera went from shooting Michael from behind, to shooting him from the front even though there's supposed to be just one camera.
It always confused me that they were filming for a reality show, yet when Jim and Pam kissed in the second season finale, Roy didn't find out about it until midway through the next season. Surely it would have aired on television? I also seem to be the only one who thinks the Superbowl episode was ridiculous. There were some funny moments, but the cold open was insane. A cat falling through the ceiling? Chairs being thrown through windows? I still like the show but it's getting incredibly broad for a "reality show".
One thing that I do admire about the show though is that they don't try to make the characters anything like the originals. I know at first they did, and there are little things such as Pam's passion for art that they incorporated into the American version but I wouldn't even bother to compare the two sets of characters. I think Steve Carell and Ricky Gervais both have their own charm; if the two characters were to ever meet I think the differences between them would really stand out. They might both be idiots, but personality wise they're really different. I do agree with you though that 30 Rock is amazing, and I would probably say it is better than The Office, but The Office is still one of the best American shows I have seen in years, despite it's flaws.
I think you made some good points here. When you really think about it, some of the stuff that doesn't get discovered by other characters and/or happens in the show is pretty unbelievable. However, tv has always had a certain level of "suspension of disbelief." The Office is no different. If they tried to make it too realistic, then I don't think it would be as brilliant as it is. I really don't care if they are stretching certain concepts of reality tv for the sake of art. This is by far one of the best shows i've ever seen. Good post though. I never really gave much thought to some of your points.