Schust,
The first thing anyone will tell you is to get a good kit and a good drummer in a great room. I'm not gonna lie, a good room is ok for a lot of metal drum sessions because the drums are usually up front while the cymbals/OHs take a backseat.
Anyways, in metal you need a great drumkit. The drums are right up front... so a lackluster kit will work I guess if you hit them properly and can tune them, but for the most part you will get weak drum tracks. I tracked subpar drums on a few songs, and they always turned out mushy, boxy, crap. No matter how much EQ I did to them, designed the transients, etc. haha. It seemed that the worse the kit, the worse the drummer was so the problem was compounded! Not timing per say, but the way the dude hit his drums... just weak and indecisive.
I've learned that if you track a drum and it sounds lacking to begin with, you're in for more work later on and the drum will never sing in the mix without samples.
So my advice is to either spend a lot of time learning to tune your drums to the best of their ability (best they will sound), and/or get a good sample library!