First of all I really want to thank you for your time and patience. It is really appreciated!!
I have decided to change my second day's tour a bit to the following:
https://goo.gl/yiNJNc
I have removed some "no way out" roads to tegernsee and to tatzlwurm but except that, I'll do the whole road from Kloster Benediktbeuern to Sudelfeldstraße.
This trip is 275km.
I'm actually not into sight seeing but indeed in for good food (doesn't matter how much it costs. Believe me, where I come from, it's more expensive for sure). First I'm into a good pork hotdog but then a good restaurant will be perfect. I'll, sure, take your recommendations.
BTW, I know it is a bit childish but I really want to know which is the best autobahn outside of Munich that I'll have the best chance to drive as fast as possible. Just for a taste. Germany is the only place in the world where there's no speed limit and I'm not sure it'll stay like that forever. I've heard before that there were people that wanted to enforce speed limit on all roads.
As for the first day, If it'll be able to go to Austria, I have added the following trip:
https://goo.gl/LvJfYd
This one is 209km so I'm still inside the 500km range and according to your recommendations I'm covering some very good driving roads in these two trips.
BTW, thanks a lot for warning me about the speed cameras. As, unlike here, it is illegal to drive with laser detector or camera's warning utilities in Germany.
OK, I'll need to leave something for my next visit :-)