I bought this car with just under 15K on the clock and it now has approximately 151K on it. It has been extremely reliable and is my 4th MB in 25 years. I current own a 2003 E430 as well. I perform most repairs myself so dealer labor costs are not usually an issue. Parts are pricey but that is to be expected for Mercedes.
Keyless entry fuel economy, timeless styling, quality of construction (10 yrs and still no rattles or squeaks!)
Regular gas would be nice and a slightly lower stance. A more robust Combination Switch (I've replaced it twice) and a different location for the power mirror switch. Heated mirrors.