I mean Tiana seemed sympathiec about his death. She even put her hand over her heart. He wasn't trying to kill her. Also the producers made it clear he only did so because his freinds were threatning him in that scene and he did state only the wayward souls.
While I don't think he's 100% evil he actually DID kill somebody. His name was Ray. And he would be a standard villain...if it weren't for the fact that he planned to offer the souls of New Orleans to his friends as payment.
As for them being his friends...well, it was indicated that he got greedy with them. Perhaps he DID wish to make it up to them though.