As you've been told, Pep left Barca because of the internal politics. The plan all along was for Pep to follow Soriano & Begiristain to City, but City winning the league title in 2012 in such dramatic fashion scuppered Pep's appointment.
Bayern was always rumoured to be just a staging post for Guardiola, just as Pellegrini was always rumoured to be a stop-gap until Pep's 3 year contract with Bayern was up.
Right now at City, he has Soriano, Begiristain, several of his old Barca coaches & back room staff with him. He has the financial backing, the infrastructure & is being allowed to build his team, his way with the players he wants.
This being the case, please tell me what any other club could offer Pep above what he has in place at City? He's said too many things about City being a 10 year project to catch up to Europe's elite teams, & him not being able to complete his project at City within his 3 year contract term for there not to be a long term dynastic plan in place.
I think you just have to accept that Guardiola came to Bayern & did his best during his 3 years there, but his final destination was always Manchester City.
I feel a few major things will happen at City over the next 12 months, so please stay in touch & let's revisit this conversation then. At this point, I believe you will get definitive answers to all your conjecture & opinions.