You have some good picks there, especially Leviathan and Powerslave. My favorite Maiden cover is either Killers or NOTB.
I don't feel like spending forever doing a GIS on all these covers, so I'll just say what my favorites are:
Dead Kennedys- In God We Trust, Inc.
Bad Religion- Suffer, The Empire Strikes First
AFI- Black Sails in the Sunset
The Clash- London Calling
Rage Against the Machine- s/t
None More Black- This is Satire
Pink Floyd- Animals
Rise Against- Revolutions Per Minute
That's about all I can think of right now.
"COLONEL KLINK, WHY HAVE YOU FORSAKEN ME?!"