You can easily get sucked in, (especially with metal, because it's so passionate) to dig in too much. But yeah, your amp is your friend, turn it up, and go with the lighter touch. You will still be able to dig in on half time sections and things like that.
Your pickups should be high enough to get a good sound, but not hitting the pickups. I anchor my thumb on the neck side corner of the neck pickup and pluck over the pickup. If you have soapbar style pickups, you can use them like a compression ramp. Raise it up high enough that you don't bottom the strings out on it, and you're fingers wont dig in too much because the pickup is there.