What you SHOULD be looking for, is whatever mic you can afford that SOUNDS GOOD TO YOU ! The reason the 57 is used so often, is that it works. It's nearly bulletproof, cheap ($79 US typically) and it works on almost everything. Yes, there are mics that work better for some things, but you'll not go wrong having at least one. I have 6 or 7 57's and every now and then think I should buy a few more.
If you want a more "metal" sound, maybe try
an ATM-25 (NOT the Pro-25) from Audio Technica. I've not tried these on stage (quit that part about 8 years ago) but they have a good strong bottom end, go to 18k on top, and can be used for bass, kick drum, lower piano, etc - That mic would give you stronger bottom end, and you could roll off the top if too bright. (And get rid of some HF noise in the process)
The main reason people hang a mic by the cord on stage is one less stand to mess with and one less thing to trip over. The sound isn't as accurate on ANY mic when you address the capsule from the side, so If you want a hotter signal and more accurate sound you should either get one of those clips that hooks on your amp for a mic, or use a stand. Then, if you're really picky about your stage sound you can try different mic-to-speaker positions to change the tonal range. Near center of the speaker gives a deeper sound, near the edge gives you "edge", etc... Steve