Laugh as much as you want but Red John will have the last smiley.

If Red John returns will the writers of the show press it hard from the beginning or will they tease us till the end?

I'd love nothing more than to have Red John come back from the get go, to watch every new episode glued to the edge of the seat, but I don't think the writers are capable of keeping that kind of tension going over the course of 13 installments. Heck, I'd be happy if they can come up with a single decent end to the Red John story line. If he is coming back it will be at the end, and they will conceal all the clues of his existence for the same length of time. IMHO

Would there be any indication or signs of his return earlier?

Perhaps. The most obvious would be to watch out for the announcement of the episode titles. Red in the title equals Jackpot! but this is just another reason I believe RJ will have to wait till the end. If they delay the name of the last episode for too long, that would be a good sign.

Also, if they make the end to last two hours (12-13) that has a promise to be epic, as well.

And the last clue for Red John's return would lie in the wedding. More precisely where would they have the ceremony? If they choose any church, then Red John might not return at all. However, if they gonna tie the knot at the Visualize church (for any reason), then I'd say the chances for Red John's return are 99.99%.

let me get this straight.  Mcallister being RJ was at Jane's house.  He planted a bomb that killed visualize.  He felt the need to move the bodies of bertram, smith, and Jane to safety just before the bomb went off.  then, a couple of days later, he changes his mind and thinks all 3 need to die?????  what kind of sense does that make???  How about NONE!!!

The Mentalist was like summer for me, in the previous seasons. It was always sunny, they showed us the lovely California. But even in this paradise, there was still something dark and creepy and everybody knew, that Red John was around, that he could be this not to special looking man, that it could be Partidge, Bertram, or just everybody, who was around. 
It had this special atmosphere, like a hot, dry somerday. It was like a beatiful world in the area of Sacramento, where crime and murder stood in opposite to everything else. 
The show was like that, a long time ago. But now, this feeling is gone and it's just a show beside a million others. 
But I still like to rember, this good old days, I will not forget them. 

Where do we go from here?*

Season 7 has only 13 episodes, but what are we going to watch in them, when Jisbon was already introduced and the season is too short to start a new arc or even a sub-plot. Will there be more pathetic FBI cases until the wedding and perhaps a honeymoon to wrap it up?

Or it will start with the partial BA list finally being deciphered, to close the book on the least interesting mystery that still remains, then jump to Stiles return. With him back the Visualize questions will be answered, then we'll have the wedding that will resemble a funeral and the final showdown with the real Red John.

If Red John is coming back I'd say they will hold him for the very last episode. We will harbor the hope until then and not complain... not really. Last episode come, it will make us either happy or very disappointed. However, by then No one will be there to listen to our complaints. I just want to prepare ya'll for the worst case scenario.

* Russ Ballard

I say 100 red johns with tongue and cheek.
The name "red john" was made up by a newspaper because
Rj was killing young red heads.
The name or person red john may of never existed with just one person using others to do their bidding.
A hypnotist. I think show blatantly displays many different styles of red john.
A computer hacker never seemed to fit Macalisters bill.

Heller on returning to the Red John story line , his followers and the Ba...

Heller: "I never say never, but I would say I think the audience and the story demands that we step away from that trope for a while".

That proves there gonna go back to it after the hiatus of lovey dovey shit.
What would you think if there was 100s of red johns?
With one mastermind pulling all the strings using others to do their bidding?
I wouldn't complain