character. Hopefully she won't be in the same camp as Count Vertigo, Deathstroke, Black Canary and Sin, who definitely didn't benefit from the changes from the comics.
What's wrong with Count Vertigo? He's probably one of my favourite Arrow villains, I was so sad when he died. Just plain awesome character! Deathstroke has literally become my favourite super villain because of Arrow, Manu Bennet is terrific! Can't disagree with you on Black Canary though, the casting was the main problem with her. But in the finale when she gave Loral her jacket, that was a nice hint she will now become Black Canary!
Count Vertigo is literally royalty from a foreign country, who has the ability to cause people to experience extreme vertigo. He was done pretty well in the first Suicide Squad comic, which was generally awesome. He's not a favorite villkain of mine by any means, but I liked him in SS and he's been a decent c-list villain (and sometimes government agent) in comics over the years. The Arrow version doesn't even slightly resemble him. I don't think the Arrow drug dealer has one thing in common with thew actual Count Vertigo, outside of his alias (they might have the same real name, I don't actually know the Arrow version's real name). Plus, the arrow version is just irritating, so he can't even redeem himself by being an interesting character that stole a name.
The actor that played Deathstroke was great. But, Deathstroke isn't a completely mental psychopath, at least when he's done well. He's had grudges before, but the Arrow version was literally insane. In the comics, deathstroke was at his best as a cold, calculating mercenary. On Arrow, he goes around killing innocent people to punish Ollie for something Oliver was not responsible for. Ivo killed Shado, and Oliver wasn't even slightly at fault for what happened. So, seeing Slade act like a complete nutjob was really disappointing, and ruined the Arrow version.
To be fair, in the comics Deathstroke was sometimes the victim of horrible writers and did some really stupid, bizarre things (like whatever the hell happened between him and his daughter Rose) but he just came off as a generic, super powered crazy guy in Arrow once he became a villain. I liked him until he went crazy, but after that he was just depressingly lame. He was definately a threat, but there was a bit too much crazy in him, and not the good kind of crazy like you'd get from a lot of Batman villains. If they hadn't made Slade crazy, and had made Shado's death more directly Oliver's fault (maybe through incompetent or some kind of hanging from a cliff type choice), then I think it could have made Slade and his revenge more interesting. But, the craziness, and the fact that Ollie really wasn't the one who killed Shado, made Arrow's version of Deathstroke pretty mediocre to me once he became a villain.