There is no problem using synchromesh and sequential shift. Most modern cars have automated shift and synchromesh which work rather quickly. The issue is a combination of our under developed synchro, poor ratio's available and the physical distance the hubs have to move.
All fixable but not easily for most.
As Duk has agreed there are electric kits available for other models but they are barely somewhat successful but I doubt on our trans. (Nor sympathetic). But dog engagement is available if you're that way inclined
Alfa hasn't performed any development on the synchro since the 60's on our trans but Porsche continued forward.

It is possible to modify the system for better, faster and more reliable shifts following some of Porsche's ideas.
Flat shift has been included in most half respectable ecu's for atleast 10 years now but I think if you're at the point of thinking about paddle shifts then flat shift is probably already being used.
The Alfa transaxle is up to the job but not as it stands now. It's an ancient design and behind the times. Fortunately the biggest obstacle is spare time and determination. (And shitballers on the internet)