You are right, I probably could use an older car under my present circumstances. When I was looking I was still doing 50k miles a year and that model was just about new enough to handle it without me worrying. Now my mileage has drastically reduced but I'm still in the big miles mindset, however, I do run my cars down to France and Spain twice a year so a real old clunker wouldn't work.
If my mileage stays this low I will probably look to swap the W211 for something like a 3 series estate petrol or equivalent c class at some point. That makes me feel old, I'll have to make sure that I go for at least 6 cylinders!