I want to preface this that I hold Jony Ive in the highest regard and his work is what gave me an appreciation for beautiful things. These are just a few "what if's" and thoughts that went through my mind on the news of Jony Ive being promoted from Senior Vice President of Design to the extraordinarily rare (for Apple) C-level Chief Design Officer.
Work and Family
I don't know Jony or his family, but if there is any family pressure to return to the U.K. then he is in a really tough position. The number of people that count on him, the number of people that directly benefit from his work, and the overall impact he has is profound. How do you balance that with a family who (hypothetically) want's to move? Of course, this "move to the U.K." is all rumor at this point. If the world is lucky, it is nothing more.
I believe it is right to pick your family over your work, but as a beneficiary of his work, I can say I will be deeply saddened when he leaves Apple.
On Replacing Jony
You can't replace Jony Ive. Just like you couldn't replace Steve Jobs. When Steve passed there were two strong rails for the Apple train to run on: the culture at the core of everything Apple does, and Jony Ive. That is how it looks from the outside, of course I don't actually know. So what happens when Jony leaves? Without Jony or Steve I think the culture will remain on autopilot for a while. It's tough to say if that will be a year or twenty years, but I think somewhere in the 3-5 year area with no un-Jony product changes is a very safe bet.
Over time culture adapts. The culture of Apple is even to adapt at its own short term expense (think iPhone cannibalizing the iPod). Inevitably the nuanced impact that both Steve and Jony have in the seemingly irrelevant details will fade. I suspect this will lead to changes in directions akin to going from skeuomorphic to flat design, and that is a good thing, this evolution is necessary.
Let's hope the rumors are wrong so that we can be selfish and bask in the benefits of a Jony Ive designed life for at least a little bit longer.
Again, this promotion could very likely have nothing to do with him leaving any time soon, but when the notion was brought up I couldn't help but consider it. I am eternally grateful for the work Jony has done and wish him nothing but happiness, whatever that means for him.