I'm surprised you count JC. Considering her ring isn't a Green Lantern power ring, but The Ring of Volthoom, from Earth-3. Also surprised to see Alan ahead of John, but I find them to be able to switch out. I'd even say Simon is just slightly ahead of Guy. (Makes me wonder why he was even created in the first place.)
My reasoning for Jessica is because even though she's a Power Ring and not a Green Lantern, it's being considered as a potato/potahto situation. She has the "Green Lantern" slot on the JL and will most likely be treated as such in the comics, which is why I consider her a Lantern, that and she is one, just not of the will power variety. As for Alan being ahead of John, Alan was the first GL and has a ton of history and a certain amount of importance within the DCU while as John, in my honest opinion, is only considered a "top" GL is because he was lucky enough to make the cut on the JL/JLU tv show.