I'll explain my thoughts on Koeman a bit, as no one here comes further than 'BRUV! hE nEaRly rElaGaTeD wItH EvErToN OMG!'
- Koeman used to be a very conservative coach - holding on to his believes, but he's become more flexible as he realize coaches nowadays no longer have years to build the line up and tactics he envisions - he still likes to hold on to lineups and tactics too long for my likings. When players have bad streaks, he stands by them and he keeps giving them playing time - I think a wake-up call and line-up juggling is needed way faster. If all the dead weight players remain in Barcelona, don't expect Koeman to bench the likes of Roberto, Busquets, Rakitic, etc, unless he's told otherwise from above of course.
- He likes the Dutch 4-3-3, but also tries modern versions - as long as he plays a broad-line-up with offense coming down the wings. Likes to play with two CDM's or at least two players who stand their ground to give him more insurance in transition. This is his biggest cryptonite - for instance; in Oranje he plays with de Roon, Wijnaldum and Frenkie de Jong - defensively they are all sound, but they all bring little creativity on the other side of the pitch. In Barcelona, he will almost certainly play Frenkie where he should and that alone should do wonders for Barca's ball possession game.
- Unlike what the media might portray; Koeman is a warm personality. The way he managed the hot mess that was Oranje two years ago is very admiring - they all care and are willing to walk the extra mile for him. With a lot of big characters in the dressingroom, I think Koeman will handle those personalities well.
- Not the coach who likes to play youngsters much, unlike they are exceptional talents or only tries them out in short stints. Ryan Babel played a crucial part in the EC-qualifiers for crying out loud (in utter disbelief, he actually played well, but still - Ryan Babel - in Oranje - as a striker - yuck). I'm not expecting Puig and Fati to suddenly start now.
- He's one of the few who learned coaching under Cruijff and while he claims his tactics and ideas are much alike those of Cruijff - it's barely visible on the pitch. The tiki-taka, short triangles and offensive pressure - it's just not there. He plays totaal voetbal (but that's a given nowadays) and plays with a high up defensive line - other than that, he doesn't have that Barca DNA Dutch coaches like Ten Hag or Bosz do possess, only they don't have the reputation Koeman has built up as a legendary defender.
- He plays his best players, utilizes his player strengths and adjust his line up and tactics accordingly. Sounds as if this can be found at page 1 in the coaches-for-dummies handout, but plenty of coaches are ignorant to this. Depay is a tough nut to crack, but Koeman utilizes him in his best role. Same goes for Frenkie. Promes and Bergwijn often have that free role on the wings. Always manages to insert Daley Blind into the lineup.
- Schreuder - Bosz' partner during Ajax' rise a few years ago, will join. Not sure he's fit as a main guy (he has the smarts, but no charisma or reputation), but he was the X-factor behind Bosz. I wanted him and Ten Hag to co-coach Ajax when he left. It appears Frenkie strongly recommended him.
- I am afraid of a Dutch enclave in Barcelona. Koeman as coach, Schreuder as his assistent, Kluivert is in control of La Masia and Jordi Cruijff is being mentioned for a role up top as well - I don't think that's ever a good idea, but I reckon Barcelona wants to bring back the Cruijff-vibe again.
- Koeman has a strong relationship with Depay. I wouldn't be shocked if Depay leaves for Barcelona this summer. Depay has the skillset that fits the Blaugrana, but he'll almost certainly not succeed there. He can't handle the criticism, the pressure or the spotlight very well - and he's always bound to disappear during (important) stretches.
- Coaching Barca has been his dream since he ever got his coaching degree. He'll do whatever it takes to succeed.
But, long story short; It all depends on how management deals with the roster. If Koeman starts with the same selection, I only expect minor success, if at all. He's not the guy who can juggle this roster into a well oiled machine. He doesn't have that Barca DNA. I do have a little more faith in his tenure if they bring in some smart acquisitions that fit his playing style with a box to box CM as a main priority.
I'd personally clean ship vigorously and cut ties with the likes of Rakitic, Roberto, Suarez, Griezmann. Don't care for Dembele much. Accept the fact that Pique and Busquets are no longer starting material. Jordi Alba should definitely stay. Not sure why I saw his name mentioned in a clean up.