I doubt the MK8 will advance any more than this has over mk7. Providing it stays within the same footprint and price bracket.
We have a Mk7 GTI here btw as comparison. I do think we will call it a Mk7.5 in years to come.
The last big leap forward was the development of the Mk5 Golf. The Mk6 was basically a big facelift. No doubt the Mk7 Golf is a more refined car in every way. The only big improvement was the progressive steering. The Mk7.5 has better tech
LED lights with Dynamic Light Assist
might be the only improvement for night time driving
Some articles are speculating that the Mk8 will have an MQB Evo chassis with further developments in Direct Chassis Control. The engines are where we could see the biggest improvements - with Miller Cycle and variable turbine geometry. These engines would have greater real world fuel economy and no turbo lag. Then there is the next generation of four wheel drive systems. Could they make one that gives the car rear wheel bias? Other manufactures are doing that!
And the biggest and easiest improvement of all - better OEM tyres.
The current generation of cars are excellent, but there is room for improvement. (especially with the tyres
)