Nice side by side. Some of the other things I noticed:
Pushers are different - both the colored top-part as well as the riveted base-part.
Pusher position is not only closer to crown (as mentioned before) but also closer to the caseback.
Caseback is missing the anti-counterfit globe .
Datefont is different.
Since the first version of the PO Chrono (quite some time ago, I did a review on that one) it seems the only real improvement was the repositioning of the subdials to the gen's layout. As far as I remember, this required extra gears on the A7750.