I doubt he will be worse than Eusebio, though both are same level of coach with one just being a bit aesthetically superior type of football.
Honestly, I've a feeling that Koeman has an under the table deal with us, but if Koeman decided to stay with NT may be Lucho coming back once his grieving is over .
Koeman turned us down once -in 2003- and he probably regret it, doubt he will repeat that again. WC in November so if he turned us down the earliest he could join us will be 2023 when he is 60. if we ever approach him again.
Would it be too much for the club to take a gamble on one of Erik ten Hag or heck even Mikel Arteta?
So much emphasis put on experience when the experience Koeman, Eusebio, Setien, Unzue possesses amounts to nothing when it comes to establishing a system and good style of play combined with results.
Arteta has no experience, but serving as Pep's assistant for three years now when Pep has undergone a transition and adaptation to the more physical nature of the Premier League while retaining his core principles is an interesting trait or experience to have.
Barca took gambles on Rijkaard and Pep, and it paid off.
Obviously it was reported recently that Txiki see Arteta as Pep's successor and he might stay there and wait it out as he's rejected other approaches, but would be something worth exploring, at least to talk with him and get a sense of his ideas.