Ok I have three thoughts.

1) Has anyone thought of the possibility that "he is mar" if finished would say "he is marked"... as in the tattoos? (this is the one that I would like feedback on)

These two are just musings
2) I think that Tolman Bunting would have been a really fun Red John.

3) i think it would have been best if the series would have ended after season three. Timothy Carter was a perfect Red John.  He was just creepy enough without being too creepy, he had the right voice, and he fit the description better that most of the current suspects.