What's wrong with always looking for ways to improve? Call it "bitching" if you want, but that's pretty much how I approach everything in life, and it's worked out great. The day I'm fully satisfied as a fan is the day I stop caring about the sport, but that won't ever happen, even if we win a SB. I'll just want another.
My point is, same as there are glass half full people, there are also glass half empty people. Same as you find people that continually defend Ireland annoying (I personally am willing to allow him 1 more year, but do understand why most want him gone), people that continually have a problem with everything are just as annoying if not more.
For the record though I don't think you fall very far on either side, there some that seem to be upset with Miami all the time, and if there is nothing bad to say, they just keep quiet until there is something to bitch about.