i will agree that "metal" is easy to play, as in the mainstream garbage they call metal. a lot of metal i like incorporates a lot of jazz and blues influences. im very picky when it comes to metal. you need to hear some real metal man..and if you want something that is challenging to play and is metal, then try:
Necrophagist, epitaph album, german technical death metal. this is like PRIMO of tech death
or for melodic metal Killswitch Engage. they have superb song structure, riffs, and lyrics. very creative. this is like SARMS
for some good old fashioned american metal, Lamb of God, ashes of the wake CD. this is like TBOL
or some good old fashioned deathcore, Through the Eyes of the Dead, Malice album. this is like DBOL
ive seen albert king before, very old school. remember i am old school lol, i used to listen to jimi hendrix, stevie ray vaughn, robert cray, metallica, pantera