No one is a bigger Fields fan than I am...I felt he should've gone 2nd in the draft and would probably even lean taking him over Lawrence today.Leftwich, Day or Harbaugh.
Arians O is tailor made for Fields.
However- what if he can't stay healthy? What if he doesn't develop into the decision maker we believe he will? If he can't stay healthy or is just a mysterious miss (or because its the Bears....) I think we'd regret picking a HC JUST for the sake of Fields. We could be in the same position we're in with Nagy.
If Fields is the stud most of us believe he is (I think he's a star)- we would just need a good football man picking his coordinators and letting them operate year to year. Whether or not its an offensive mind that fits Fields should only be a reason as to why you hired that candidate, but not the primary reason.