I would not consider any of these repairs excessive.
If you had a 15 yr old GM or other American car, you would have a repair list twice as long. The car would also be ready for retirement.
Your MB should be good for another 15 yrs at least!
The main thing is to look at the repairs you've made.... they make the car better. If you buy another, unless it is in perfect condition, chances are you will have to make about half these repairs on the new one, and more later. This will make you wish you still had the 190.
Enjoy your ride!
Buy another if you want another, but I wouldn't part with the 190 if I had put that much into it and it ran well....
Just my 2 cents....
76 240D (W115) - 555K miles
78 300D (W123) - 200K+ miles -- SOLD