Tim would be a GREAT CEO at Dell.
There are others who could be okay and better CEOs for Apple, but it would be unlikely to find somebody who would be GREAT at controlling one of the largest corporations in the world with brilliant, but extremely opinionated executives.
Only a guy like Jobs had the clout and respect as a former founder to step into Apple during its time of near bankruptcy to enact every one of his ideas without resistance.
I’d still rather Apple play the CEO lottery and hope to find a visionary with the ability to have others develop confidence in his/her vision.
Just being theoretical, If there was anyone to replace Cook, I think it would be Jeff Williams personally, he seems to have the mindset and leadership capabilities through Apples DNA.