Though it goes without saying that many replies are going to be Ronnie.
As much as I love Ronnie, when it comes to the rest of the band as a whole, I think I'd say Jacky.
I've noticed when many people refer to Falling In Reverse, they're only talking about Ronnie and what he's done and completely ignore the fact that Falling In Reverse is a band with five members.
It's always been a pet peeve of mine, how the singer, even though the leader for the band, is usually the one to get most of the attention from a band's fans.
So consider everyone else before you start shouting Ronnie Radke ^^