With or without Doncic I think Phoenix will be bad again next season. I can see them drafting Doncic who stays in Europe another season and Phoenix gets another top-3 pick.
Doncic has a relationship with the Suns coach so I wouldn't be shocked if that happened. I think that would work out well for the Kings since I think Ayton would be a slightly better fit for them. Doncic would also be a great fit for the Suns alongside Booker.