This is going to seem like a sacrilege to some, but hear me out.
With six of them now, DC has proved that it's got far more Earth Lanterns than it has any idea what to do with (and thanks a lot for that, Geoff), so maybe turning Hal into Parallax for keeps would be a good idea.
Unlike the first time it was tried, this would not entail the gratuitous and pointless destruction of the Green Lantern Corps and the Guardians.
And there would actually be a method to the madness this time, instead of DC's doing it simply for shock value and as an excuse to create another Earth Lantern. Parallax was a very good villain, at this point less would surely be more where the Earth Lanterns are concerned.
Of course if it didn't sell it could be undone, but I bet it would sell fine.
(Do this and also find another job for Baz and Cruz, and the property would really start rolling. But that's a separate subject.)