But, I could understand why I don't get along well with metal, I was born and raised on classical music, trained on piano starting at 6 years old, up to 15 when I added pure jazz (was in love with jazz way before learning/playing it though), so, quite far away from metal.
I thought I was going to stay out of this thread entirely but I'm going to pile on to your quote as well. Sorry.
There is a whole subgenre, called symphonic metal, heavily inspired by classical music. The band Symphony X does it best, IMO. No growling vocals (he can actually sing), incredible guitars/synth, and one of my favorite drummers, Jason Rullo.
Here's a short little tune based on the epic poem by Homer: