I think the appointment of Ange & the lack of European football means we're in for a full rebuild, with an emphasis on a high energy game & creating a positive, peak Poch, culture at the club.
Kane wil llikely say "I don't have time for a rebuild & want to win trophies & play CL now". If he's prepared to move his family to Spain, then Levy will get the best deal possible out of RealMad to ensure yanited's ordinary team isn't massively upgraded by the signing of H.
We will desperately miss Kane's goals & creativity. But Ange will then have a freer hand to create a high press, high energy, tactically flexible team like his Celtic formations.
Ange's first task will be to rapidly decide whether any of our expensive returning midfield loanees - Ndomble, GLC, Winks - can be part of his system and culture. If not, get them out asap for as much as we can.
And deciding what we're doing in the FB/WB area. Is Perisic leaving? Are Porro, Udogie, Reguilon & Sess suitable for his system?
And, crucially, who plays CB with Romero.?
If Kane leaves, I think Richarlison will be given the opportunity to be the new CF fulcrum. He is Brazil's Number 9. Psychologically, if Ange tells Richarlison he's now the main man and he's relying on him, then we know he'll give his best. And Richarlison will probably have until Xmas to demonstrate whether he can thrive in the new system with the new responsibility.
If he can't, then the rebuild will continue.