I guess when I was thinking about classical vs. rock in my original post, I was thinking about good rock, as mentioned by many, the progressive rock bands (The Doors, Black Sabbath, Pink Floyd, Led Zeppelin etc). I can see some Blues influence, but not so much as Classical influence, especially in the melodies. I consider groups like the Beatles to have much more blues influence than the progressive bands that did indeed pave the way for more contemporary metal.
I think that for new, really good music, people need to just forget about genres, styles other groups have been labeled under, and past techniques. I think music is much more pure when basic structures+personal ingenuity and inventiveness and of course natural artisticness all meet up. That's what made so many groups in the past great. When reading interviews with bands, their personal favorites sound much much different than the music they make themselves. Maybe too many people have stuck to the formula way too much over time. Then again, metalheads often complain about anything that actually does end up sounding different. I think there are a lot of hurdles for newer musical groups to get through that make it almost impossible to even sit down and create good music.What's the process for uncluttering any artistic process? Sticking with what's good and ignoring the rest? Or maybe simply ignoring any and all other opinions and just creating.