I dig punk. I have absolutely nothing against punk, hardcore, crust, whatever. Hell, I even like Turbonegro. I haven't heard extensive amounts of punk, but I have heard Bad Brains and Cro Mags. I liked Bad Brains, Cro Mags didn't really do anything for me...but I have nothing against any form of punk. As for metalcore, I have a deep resentment of the genre that comes from being forced to sit through several metalcore bands at every show I go to. Musically, I don't like most of it, but some of it (like Chimaira) I like.real hardcore punk and metalcore are actually good. I doubt you've even listened to bands like Iceburn, Cro Mags, Quicksand and Bad Brains.
Nobody respects Slayer anymore. They haven't produced anything worth listening to repeatedly in a while. I liked parts of Christ Illusion, but if you want good modern thrash metal Kreator is the place to go.Then again... Slayer has a song called "God Hates us All"
You mentioned digging black and death metal, so while I'm not an authority on either of those genres...
Death:
Bloodbath
Vital Remains
Behemoth (later)
Morbid Angel
Death
Cannibal Corpse
Bolt Thrower
Black:
Bathory
Immortal
Gorgoroth
Emperor
Behemoth (Early)
Summoning (Probably a little too chill for you)
Behemoth and Bloodbath have more of a modern sound than the others, which are more old school death. Vital Remains is pretty raw, but great. Check out Dechristianize.