Was Catiline not quite as much of a treacherous scumbag as Cicero made him out to be? Maybe. But I think you'd be hard-pressed to find a way to portray Catiline as a hero. There are classicists that argue that Cicero's rhetoric shows a much nastier Catiline than actually existed, and there's some merit to the thought. But nobody thinks Catiline was a hero, or that he started his conspiracy out of any sort of moral righteousness or to actually help anybody. It's extremely clear that Catiline got the conspiracy rolling out of his own personal desire for the consulship and his repeated failures at election. The central part of Catiline's populist program, the mass cancellation of debt (which, mind you, was probably not nearly so populist as if may sound--many of Catiline's supporters were indebted aristocrats and many of the rest of them were old Sullans who had been forced off their lands), was highly popular but was only taken up by Catiline late in 63. Meanwhile, he had gotten the ball rolling on the conspiracy in July of that year, after he found that he had lost the election for consul for the second year in a row, by instructing Gaius Manlius to prepare an army at Faesulae while other conspirators started uprisings in Apulia. No matter how much of a real threat to the state Catiline was (and he was pretty incompetent) there's pretty much universal agreement that his conspiracy was begun purely for selfish reasons, in response to the dolor of repeated electoral failure. That the people who supported him were aware of this is also abundantly clear, as Catiline rapidly lost the favor of the masses starting in November