I write reviews for thrashpit.com as well, and many of the reviews here can be found on that site as well. My username is Prog Prince. Although metal is mostly what I listen to, I also enjoy just about everything else to varying degrees. As many of said, if you are truly into metal you kinda have to be open to variety in music since metal itself is highly variable.
One thing that bugs me about metal nowadays is that it's branching off into too many subgenres and such. There may come a point in time where everything is too confusing and there's too much grey area. For example, the fact that we have identifiable genres such as 'hatecore' and 'pornogrind' seems to be reeking of too much attention to detail.
Another bone of contention is the fact that all the metal band shirts seem to be black for the most part. I've spotted a grey Meshuggah shirt once, but most of them seem to be black and that bugs me because there are other colors out there and the singularity of color dominance of the metal culture seems to make it seem that everything in metal is about darkness and rebellion, which simply isn't true. Plus, it seems to foster a sense of conformity, when metal is supposed to be about individuality for the most part.