It is intersting how little semi-automatic handguns have improved since the 1911. I like alot of non-1911s, don't get me wrong, but it is food for thought:
Almost all of them use the same operating principle as the 1911. The swinging link is usually replaced with a solid cam-type deal like a BHP, but functionally there is no difference. Some lockup in the ejection port instead of using lugs, but that has the disadvantage of making the slide blockier and bulkier. Double-stack mags are nice (hey, Browning stuck 'em in the BHP), but they compromise the ergonomics and increase bulk. Bushings are no longer "in" for barrels, but aside from simplifying manufacturing bushingless barrels don't really do anything special for you. And while DA and DAO and Safe Action triggers may be more lawyer resistant, they sure don't help you actually
hit the target compared to a good SA trigger.
It would be fun to speculate on what Browning would do different...?
Titanium frame and forged 4340 carbon steel slide and small parts with some wonder finish like NP3, tennifer or hard chrome
Linkless
and bushingless barrel system
Modern high-visibility sights
No grip safety or spur-type hammer that could bite
Possibly a different extractor design (though I think JMB would be smart enough to avoid that modern "innovation" known as MIM that makes the old extractor design look bad in the first place...
)
The trigger would be single action with a crisp pull, but since he was an excellent salesman he'd call it something else to make it sell better in the 21st century, something like "the patented fail-safe triple block trigger system (TBTS)," or something
Models in different calibers would have modifications from the factory to insure correct timing and reliable extraction in the higher-end calibers like 10mm and 9x23 that he'd certainly embrace.