I'll agree with you about Grunge. We'll have to agree to disagree on the best band because it was actually Alice in Chains. Not to take anything away from Nirvana, but AiC was far better musically and the harmonies were from another place altogether. And if you want to talk about voice, then we are both wrong because that would have been Chris Cornell. Sadly, the only remaining lead singer from that genre is Eddie Vedder.
RIP Layne, Kurt, Chris, Scott, and Andy