In all honesty there is no safe or obvious choice.
1-No big name coach will arrive next season, Allegri,Pep and Klopp are settled like kings in their clubs. Conte is declining name and same for Mou, Pochettino and Simeone will never coach us, Ancelotti and Zidane won't come either. Can't think of another name that can be considered "big name". Tuchel on his way to PSG
2-After that there is the "exciting" names that aren't so exciting tbh. Sarri and Setien who spent most of their career coaching lower teams and only started coaching respectable team recently while they are close to their 60's, never managed super stars before or even experienced being one or playing beside one. As Xavi once said that coaching this days depends a lot on man management more than anything.
3-The Barca DNA, prepare yourself of the Cocu, Unzue,Eusebio candidates
4-The "promotion"type of coach like Marcelino, can't think of other names in Spanish football right now, but they are mostly just like EV, they can produce some respectable football but fans will sooner or later will turn against them.
Overall I would understand the board decision to take another bet on EV with season double (or just league) over other gambles. If there was an obvious choice I think they would have thought of it.
I am not against Cocu. He seems to be doing fine managing PSV and was Barca captain. Being Dutch brings us back to Cruyff's legacy too.