Thanks for the vote of confidence, but my personal opinion after watching this team for two decades is that once Messi is gone or stops being the goat, you will see us enter the United/Moyes zone.
It will be probably worse than 2013, after we lost Guardiola and he dragged an awful team that deserved to be out in both round of 16 and quarterfinals, but Messi scored two goals vs Milan to lead the comeback and came in as a sub in the 2nd leg vs PSG without being 100%, giving Pedro the assist that classified us to be destroyed by Bayern that year.
He's dragging our corpse (and Argentina too) for some years in his career, Ronaldo does it but in a different way, he doesn't need to be involved in the play as much, he just needs to score, and he does it like Messi. But since Guardiola departure, Xavi's worst years and now Iniesta's decline he's the only elite creative player (bar Rakitic, who is wasted largely on defensive duties) between our defenders and Neymar/Suarez, first treble Messi had a 24% goal participation of the team, in 2013/14 he was already above 40%.
By the time Messi (29) retires, only Umtiti (23) and Neymar (25) could be stars to build around already in the club. You can win a treble with Messi and 3/4 more elite caliber players as Lucho did in the first year, but I doubt you can do the same with Neymar, he needs to take a huge step forward to fill that role for a whole season.
Once Ronaldo retires, well he's already 32, and Asensio, Varane, James, Casemiro and Isco are still under 25, Kroos and Bale are 27 y/o so they still cover with Ronaldo the age gap between Messi/Neymar. Madrid are set for a better future and, worst case scenario, they will have to splash the money into a great goalscorer, which is what Ronaldo has been doing the last years, with Messi you need to cover the void Ronaldo would leave, and then some more work in the engine room without having players like Marcelo, Isco, James, Modric or Kroos to feed him.
We'll see, but for me Messi is to Barcelona what Ferguson was to United, that's why he's the first "best player in the world" we've enjoyed for more than five years. Cruyff, Maradona, Romario, Ronaldo, Rivaldo or Ronaldinho, we burned all of them in five years or less and almost all of them started a crisis once they left the club, imagine what will happen once Messi goes.
For the leader part, there's a lot of kinds. Tim Duncan was a "shy" and silent guy, and he was Spurs' leader for almost 20 years. Garnett was all heart, antics and a lot of talking about leadership, but he "sold" his teammated for a chance in Celtics, and then also left the Celtics for Brooklyn. You see them in videos and Garnett strikes you as the best leader, yet Duncan did a better job at leading his team for a better part of his whole career
