While Lucho wasn't perfect by all means he didn't have like you said that personality and authority that Valverde lacks.
One of the things I noticed in his final season is that he started to have some doubts about Rakitic and decided to give Gomes a run of games instead. Lucho even commented during a press conference after an interview Rakitic had made before he lost some promience saying "He doubts Rakitic will jump off a cliff for him anymore" Rakitic made a comment saying "I will jump off a cliff for Lucho" to add context.
It was only after Iniesta's long term knee injury and Gomes not exactly being that great Rakitic got his spot back. I remember the rumors during January, that City were heavily interested in him and I still think it was Rakitic and his agents leaking info to MD/Sport to try and pressure Lucho to play him as a starter again.
And add insult to injury that season, Alba was throwing a fit after we switched to a 3-4-3 for a short time and he got benched due to it. Alba was praising Lucho before, but after we switched to a back three, he suddenly thought Lucho was commiting murder after he left him on the bench. I mean what can Lucho do? Alba was way to small to play as a CB in a back three.
I can't imagine the shithousery that would happen of Koeman was our manager. He's another one that has that "I don't take shit from no one menality"
Those are exactly examples of situations where many problems, in particular in a successful team with very accomplished players, emerge.
When the manager clashes with the team (not talking about single isolated incidents which occur on a weekly basis) it is usually with the senior players or the core of the team. The ones that have the biggest say in the dressing room, the most accomplished guys and those that in theory can contribute greatly to a possible dismissal of a manager or him turning into a success story.
My theory is that Lucho, much like Pep before him, wanted to replace some of the seniors to create renewed hunger, more dynamism and prevent complacency. However the board was probably not on the same page (in particular not given the spending back in 2014) and because it is
always easier for the board to replace the manager than a core of the team or many individual players.
I am not sure if you remember but there were very strong rumors about Pep wanting to sell numerous profiles back in 2011 (Piqué being one of them) for those same very reasons and probably others as well.
As for the Alba example, it's just a perfect example. He has played his best football ever since his fallout with Lucho. Arguably. Prior to not being called up by Lucho for the national team, he played maybe his best ever football. Because there was something on the line. Someone (Lucho) had bothered him so he wanted to prove Lucho wrong. That kick in the ass in other words that players and most of us need in our daily life in certain areas. To spark that inner fire that can make us do the extra push etc.
If the club decides to appoint a manager for a long-term project (or at long as they usually last which is some 3 years) I would prefer a change of SOME of the seniors. More fresh blood is needed. I would certainly part ways with the likes of Rakitic, possibly Pique and Suárez. Of course provided that the club is able to buy sufficient replacements which is easier said than done. But in theory, if I could replace all 3 with say de Light, de Jong and Mbappe (just examples) I would do it in a heartbeat like most others. Less can do as well.
Honestly, if not for Pochettino's perico past, I would take him in a hardbeat as I believe that he ticks a lot of boxes. That or someone obsessed with football like Henry. I really believe that the latter could do a brilliant job honestly. It would be a gamble but he was/is one of the better students of Pep, knows the club very well, knows Pep very well, the Cruyff school, is pragmatic (due to his time in Italy and England), is obsessed with football, would be a very respected figure and personality, he has that aura of respect about him similar to Zidane etc. The only problem is his lack of experience at the highest level (his hard time at Monaco might help him grow a thick skin as a manager) and him having played with some of our remaining seniors (Messi, Piqué and Busquets).
Actually a bit shocked that only 3 guys are left from the 2009-10 squad.
How fast time flies by. The usual cliché but damn, it's true.
BTW much of what I have talked about also applies to business.
Lastly, this is also what I eluded to initially after my return here when I wrote in the Valverde thread that the problems and challenges are not all on Valverde himself but that they go deeper than that. It was more to put a slightly different perspective on what people wrote in this thread rather than a "defense" of Valverde as a manager or me somehow being in love with him..