Green Goblin (Norman Osborn) - The perfect villain for Spiderman. He's his best friend's dad, he's used and abused his powers with almost a complete lack of responsibility of any kind other than to himself and its don't nothing but work for him. He's rich and powerful and completely insane when it comes to pure lust for power and hatred of spiderman. The one man that beats him. He's turned destroying Parker's life into an all consuming fate of his life in the past. Playing chess with Peter's mind, friends, family, and even destroying his own son Harry to accomplish it.
People all love Venom as do I but Norman is Peter's one true Nemesis!
Angelus - Imagine your worst enemy, your greatest fear and worst nightmare is you! Now in reality this is actually true about most of us deep down. No one sabotages or destroys our own hopes dreams and over all lives better than ourselves but in Angel's case its so literally true that he actually kills everyone that matters to him and countless that don't when he gains true happiness. He really is another person within himself. And yet he can't even attribute it to something as controversial as a split personality because its him. His evil side is still him making all the decisions and taking pleasure in all the pain he inflects. He's even admitted to enjoying it when he's "free" but he wants nothing more than to pay for all the crimes he's committed and stop that part of himself forever.
Just Imagine what you'd do or be capable of doing if you no longer had any guilt, morality or conscious to hold you back. Then what would you do if after 200 years or so you felt it all again for the first time!
A lesser man would've killed himself quickly but Angel choices to live with his past and attempt to atone for it. While knowing the risk he takes in that if he is ever allowed to experience happiness or true joy again he will become that which he hates the most and lose all he's gained all over again.
Deathstroke - Cause he's ****ing awesome. He's Captain America if he was a badguy with a awesome attitude of control and style.
Black Adam - Alright I don't really see him as a villain. Just a hero who is not gonna play everyone else's politics. He was born and raised the old school eye for an eye and while I don't personally agree with that philosophy as a whole I do see and believe Adam is right in allot of what he does that the others condemn him for.
Lex - Because God I hate Superman and want someone to put him in his place. We all know that if it ever gets done Lex is the one thats gonna do it. Now I don't like the megalomaniac senseless killer versions of Lex but the are other version's of Lex that aren't so much black as just really dark shades of grey that I really enjoy hoping get to hand Supeman his ass one day. Michael Rosenbaum in the earily seasons of Smallville anyone? The current Green Arrow's dialogue with Clark now speaks my feelings for it all best thou.