I mean, recruitment first and foremost is felt out via the actions of the hero. Do they show regret? Do they show desire to change? Really for most good people? You just need to show them the good work the Korps does, and they'll want to change sides, but the Korps is not all smooth magenta glass, and dark chrome. There are messy parts of the mission, so the promise of a better world may be tainted in their eyes, so certainly filters need to be used.
At the end of the day, RCGs do a hell of a job letting the whole of the Korps leadership structure know the actual truth of a person's intentions. If they don't want to play ball, and put on the visor? Well, there is likely a long process... I bet someone like @VisorVixens has some ideas about that...
The elevator pitch for recruitment though? The goal that encourages them to join is usually enough. There is a greater good situation here certainly, you'd have to be willfully ignorant to not see it, not to mention the simple fact that the Korps means the freedom to be yourself, and to know that you could help give that gift to everyone? Is there a greater good than that?
Not in my eyes. Again, this is my take, I am not the whole Korps, but this is what made me want to be a villain~!

