The old Rolex clasp did indeed leave something to be desired.
The old Rolex clasp is made of pressed sheet-metal (or sheet gold) and came as a flat piece of metal that was pressed and moulded into its clasp-like shape. The actual "clicking" mechanism that secures this clasp is actually based on a friction system.
The new Rolex clasp is made of a solid piece of metal that has been drilled out. It starts as a solid block, then a mechanical drill literally drills out excess metal until a clasp is formed. The actual "clicking" mechanism that secures this clasp is based on a mechanical system.
Rolex is improving its line-up bit by bit, first we started with the solid end-links and now we've improved the clasp. I wonder what they'll think of next because they've already fulfilled my two suggestions.
I wish I could think of some way to improve the crown. Possibly (big maybe) have crown protectors on the case in a subtle way for the normal Datejust models (like the Patek 5127's crown protectors).
As you can tell, these are weak suggestions. The Rolex watches are truly nearing perfection.