Originally Posted by Antares
The 2 series Coupe should be larger (to provide more shoulder room for driver and the front passenger). The technicians took the 1 series and made it to Coupe to save costs, and this is visible.
As it is now, it's cramped. I have already discussed this over a month ago, so there is no point going back into the details.
A shortened 4 series would be a far better solution and far more premium.
A second thing is the form; the car would be far more spacious and practical for every day use if the Coupe would have a Ferrari Berlinetta (or Hyundai Veloster as Scott26 described the form) rear end.
In big companies it is so, that replicating existing forms gets a green light far easier than introducing something new; as a result there are cars like 6er Coupe (instead of making a sports car in the marvelous form of M8 concept a fish came out) and a pregnant Coupe aka 3er-GT.
The elegant sporty 3er Coupe was stretched into 6er Coupe and made pregnant into a 5 door 3er-GT.
The current 1 series has plenty of room for me. Also, none of what you mention is new. Companies have been leveraging economies of scale by using shared platforms for many years now.