I guess to combine the best of both worlds, you'd need to design a traditional manual gearbox and clutch combination, but with robotic automation like a DSG, where the gear linkages and clutch can be operated automatically. Have the car operate as a manual most of the time - gearstick and clutch pedal - but have a switch which locks out the stick and pedal when in "automatic" mode, and they are then operated robotically and completely automatically. You could get the advantages of easy automatic driving most of the time, and then true manual gear/clutch operation when you want the involvement.
It will never happen though. I guess it would be heavier than a DSG, more complicated and more expensive. Not to mention some of the practicalities of switching seamlessly between manual/automatic mode when you have a physical gear stick to consider. Not impossible, but I imagine the market for people who want a completely manual transmission for fun but who wouldn't find a DSG or similar a decent compromise, is very small.