#1
Ok So my current rig setup would be a 6505+ with a marshall 1960a cab and a maxon od808 to give me a little more ooomf but i'm really thinking about switching my rig because i just don't know if this tone is for me. My options thinking so far are moving to krank rev or maybe keeping the 6505 and moving to just a krank cab, i've also taken mesa into consideration about trying a mesa cab with my amp or an entire mesa setting. I'm a big fan of bands sound like shadows fall, all that remains, killswitch engage, and in flames this is live sound i am talking about. I know I should be getting that perfect in flames tone but just thinkin about something new and need input. Any advice? thanks
My Gear:
LTD EC-1000 (duncan jb/jazz)
Schecter SLS (EMGs)
ESP Horizon
6505 head
Marshall 1960lead cab
Boss noise gate
maxon od808
boss chorus
boss de-7
Dunlop strings and tortex 1.14s
#2
If you want their sound get there gear. Here are some links to the gear the bands you listed use. Hope this helps.

Shadows fall-
http://www.uberproaudio.com/content/view/144/38/
http://www.uberproaudio.com/content/view/244/38/

Killswitch engage-
http://www.uberproaudio.com/content/view/401/38/
http://www.uberproaudio.com/content/view/16/38/

All that remains-
http://www.uberproaudio.com/content/view/366/38/
#3
Do a speaker swap! The 1960a cabs aren't as good as the 1960av cabs (w/celestion vintage 30s.) The 6505 should be able to do those tones pretty well. You could try the Rev+ if there's any in stock around you, I could never 'krank' it to get what i'd be hearing in our rehearsal space though at the stores here