Congratulations on these acceptances – you sound very talented.
A few questions:
Have you had the opportunity to visit any of the campuses in person?
Is there a particular professor that you hope to work with at any of them? (as opposed to the overall prestige of the program). That sometimes can sway a decision.
Is the job you have set up afterwards in the U.S.?
If your intent is to have an MS with thesis, then the research that the professors at each university do is important. if your degree is coursework only, then it is likely that any of these three programs are fine. Cornell is outside a major metropolitan area so that is a big difference compared to the other two.
Think of it this way, you are likely to be there only for 2 years at the most. If you are trying to keep the costs down then take Georgia Tech. It is an excellent school and Altanta is a nice city to live in as well. You can always take a vacation and visit California.
I’d take Cornell out the equation…great school but Berkeley & Tech are its equals (it not better) and – logistically speaking – it’s simply easier/cheaper to fly directly to Atlanta/SF from Europe rather than having to make your way to Ithaca.
Then the choice becomes harder…Tech is the #1 industrial design grad program in the country…but Berkeley is #3 so I think we can safely say that both are great . I would tend towards Tech – great campus, great city – rather than taking on $20,000 in loans…on the other hand, you’re going into a strong field with a job already in hand so you’d like not have a huge burden paying it off. But I’d still go Tech.