There is a lot to be learned about all the features in the Self Study Programmes which can be found here
Massage is nice (I think) but distracting whilst driving. It is only present on 18 way adjustable seats.
The "Tempomat" comes in two varieties: normal and adaptive (with a radar distance measuring device in the front. The speed is shown in the infoscreen on the dash and prsented on the speedometer with red lights at the set speed (which looks really premium I think).
You do not need more power...
This car is made for ultra-comfortable (ultra-) high speed cruising, not for races at the traffic light.
Hope this helps.
If you want luxury, comfort and preferably have an Autobahn to sometimes enjoy 250+ kph this car cannot be beaten.
Fuel economy is like the Greek economy but you probably already guessed that.