Constantine seems like a natural replacement should they ever cancel Supernatural.
They should have just done that this year, considering Supernatural could have had a near perfect pilot-to-finale wrapup with the Season 11 ending with such minor tweaks its ridiculous. There is nowhere else to take the story. I love the show, but honestly feel that this would have been the perfect time to retire SN and allow Constantine to make a 5 day a week DCU.... would have been fitting, considering how much Hellblazer inspired Sn to begin with.