YHVH is vain and inattentive to the point of letting his angels fuck up humanity (SMT1, SMT2), and then lacking enough perspective to think saving a handful and wiping out the rest is okay (SMT2),
again by original myth despite a promise not to do so again in said myth (the ark), so he also is either forgetful or doesn't honor promises. If I recall, even Gabriel urges Aleph to stop him at that point, if he's Law.
Lucifer is a manipulative, destructive being who would do anything to have a chance at defeating his enemy, even to the point of destroying the entire multiverse and bringing time itself to a halt (Nocturne), killing the humans he seems to care so much about (SMT2).
Not So Different, anyone?
...So fuck you both, I'm Neutral forever.