Maich,
Buckethead is way post rock'n'roll and even new wave either. He's definitely genius and superb guitar player. I've never listened to his solo albums, but I heard him with Bill Laswell live and recorded. In both cases they sound fantastic. If you like Buckethead and further "heavy stuff not so boring as Metallica", you should definitely check out Magma and also solo albums of Christian and Maurice Vander that are band leaders. You'll be lucky if you get these albums (CDs or records) bellow $30, but this is like an investment to paintings: it'll never drop bellow unless the condition of media gets worse. Check the heavy noise stuff by Goz of Kermeur!
To classic Rock'n'Roll such as Led Zeppelin, Cream, Genesis, most of Jethro Tull, some of Supertramp I'd use tone controlls. King Crimson stuff seems to be in very good shape except their first two albums.
Almost all punk of 80's doesn't need tone controlls.
