Great question which I'm sure will be debated in the years to come. From what I've read on the internet (which must be true, right?) the suspension bushings were softened after 2014. I have no proof of that, of course. Otherwise, I don't even recall reading or hearing about any other changes besides Sync 3, which you already mentioned.
I'm subb'd for updates, though, because I'd like to know myself.
Oh, and can I say that anyone who has an NSX and a FiST must have good taste