The right snare drum can make a difference, too.
For recording, I often like a 13". The sound coming off a drum like this is often ready-to-go and won't require much processing in the mix unless you want that steely-dan "tic" snare drum sound. I keep a wood one around with a Remo Fibreskin head for a warmer/dryer sound, and I have a Tama Steel one with an Aquarian Hi-Energy for something with a lot of crack.
If I have to record a weak-ass player or I want a deeper rock sound I put my Zildjian Alloy snare drum in there. It's loud. Really loud.
But, the best advice I can give you is "if 80+% of your snare drum soud isn't coming from the overheads, get a new drummer!"
Here's the deal: If the drummer doesn't *hit* the snare, it still sounds like a weak snare. The 13" drums are cool because they are small and sound like they are being completely just taken over, owned and shown who's the man without having to hit quite so hard. This sound drives the energy of a song.
Think of it like this: You know how when you have a sample of a rock snare and you turn it down in the mix so it's nice and soft for a ballad? Sounds completely wrong, right? I mean, you have this *crack*, or this *beef*, and what it amounts to is a snare drum that's being played at the top of it's range but turned down in the mix to not be too loud. It sounds absolutely *goofball*.
The reverse is also true. There's almost no point in close micing a snare to make it loud for a metal song if the guy isn't HITTING the snare to make the right kind of sound in the first place. If you have a guy with a left-hand pussy, I'd suggest using a v-drum pad for his snare and just trigger the right sound. At least you get something.
Now I'm rambling. Recording crappy drummers sucks.