I actually got the 1CC on Hard for Final Vendetta! Right down to the last life! My overall ranks is a B, but I do not care. The ranking system is ass, but at least I beat my high score with 3,100, 000 points. I used Duke because he has the best and easiest to use juggle moves. Duke is a combination of Adam and Axel, which is another reason why I favor him.
This game I am putting down for a while, until they patch the console versions. The Steam version already has the patch update, but I am not dropping another $20+ for features that should have been in the game at the start. The last boss I still don't like, even when you know the pattern and how it works. But I hate the 4th boss, "The Gentleman" (Randy Savage knock off), even more. If you're playing as Duke or Claire, there are exploits to beat his overpowered ass, but good luck with trying of with Miller. Unless you're doing co-op, you might get lucky.