In the first Austin Powers movie, the main character has to go through emotional changes which helped to raise the comedy and character to another level. That's what's great about it. For the second movie, all of that is just gleefully thrown out the window. There is little to no further development of these characters until the third Austin Powers movie. So, watch the second one for the jokes and the songs by Dr. Evil and Mini-me, but don't expect it to be as good as the first one. (Don't get me wrong, It was good just not as good.)
The strongest suit about this movie is that Myers spent a lot of time developing the quirks of his supporting cast and villians, so in the end they were much more interesting than Powers. Mini Me, for instance, was a brilliant joke that didn't stop and Scott Evil's sarcastic skewering of his clueless father was marvelous. Fat Bastard was also hilarious and inspired, and I would say overall the film was satisfying.