You've gotten a lot of tips and I agree with the bulk of it. I can sum up some of the things I try to think of, most of which has already been mentioned.
(Just a quick background-check: I run a metal studio since 15 years back and has worked with numerous acts mostly in the black and death metal scene. Since you mentioned metal recording, I though my experience might be of some help. With that said, I'd like to point out that I take a different approach when I work with this kind of music that will not be suitable for other things.)
1. Use new heads (goes without saying) and make sure they are tuned properly. If possible, match the choice of heads to the playing style of the drummer. Soft hitter: Diplomat or Ambassador (they open up easier). DEFINITELY not pin stripe (will kill the attack too much). Hard hitter: Emperor or Pin Stripe.
2. DO NOT muffle the drums unless you really have to! You take away some of the sustain which is usually why people muffle, but you also take away a lot of the attack.
3. Be very careful with mic positioning. The less EQ you have to use the better of course. Proximity effect can mess things up or it can be beneficial. It depends so much on the drummer. (Been using SM57 for ages but I just bought some Sennheiser e604's, trying them out on the current production. Very easy to position and the sound seems to be perfect for what I do)
4. Using trigger mics (in combination with the "real" mics) on the toms will save you a lot of time (see below)
5. Get samples of the kit BEFORE you start recording! I've learned this the hard way. Make sure that you get good, hard and consistent hits. (Use these samples also to match the tuning now and then during the session)
6. Use gates on the toms, set them pretty tight. Use the signal from the trigger mics to trigger the gates. It will save you HOURS of editing.
7. Use the signal from the trigger mics to trigger the samples you recorded. Use at least 7-8 samples from each drum, played randomly. You can use very little dynamics for this.
8. Blend the real signal with the samples according to the playing. Inconsistent, soft hitter: more samples. Consistent, hard hitter: less samples.
9. You will usually have to cut out a lot of low-mid, as you probably already know. But instead of boosting high-end, try to cut out low-end instead. If you still want to boost high-end, try to do it fairly wide.
10. The above also applies to the samples, but it's naturally much easier to add high-end for those! I generally eq the samples much less than the miced signal.
11. Don't compress the toms too much. Some mentioned long attack time: fair enough if you want to accentuate the attack of the drum, but that's not always the case at all. The L1 approach isn't bad but don't overdo it. Better yet, use a compressor with lower ratio and don't hit it too hard. See the samples more as a kind of compressor and keep the miced signal fairly dynamic.
12. Send more of the samples to the reverb than the miced signal.
13. The more you use of the samples, the more editing will probably have to be done (especially since inconsistent, soft hitters usually play sloppier in general).
Ok, I might edit this but it's what I came up with from the top of my head. Maybe someone will say that I'm WRONG now or something but A) this works for me, and B) we're talking metal. The drums usually have to cut through a thick carpet of heavily distorted guitars, so the task needs to be approached in that way.
I can also point out that very often I will not use samples on the drums at all, but it requires a very good drummer. In these cases, and if the time allows it, I sometimes crossfade the last hit in a fill (or wherever needed) with samples to get a nice sustain without cymbal bleed.
Hope this can be of some help!
