I agree entirely. I am personally arriving at more refined and larger cars as time goes on, and will likely eventually wind up in an powerful S-Class if not bigger. The 535d is already at a point for me where it's ability to make progress is more than enough but the ride and comfort is probably less than ideal.
The reason I settled on it anyway was because there's nothing else in the £15-20k price range that has the same fuel effeciency and power level. If I could have upped budget to £25k I could manage an XF 3.0D, but it's 20% down on power, and while it's only £5k more than a 535d the TCO impact is much larger, as it's a newer car and in a steeper section of the depreciation curve and general residuals are weaker. The Audi and Merc offerings are not even worth considering.
The reason I settled on it anyway was because there's nothing else in the £15-20k price range that has the same fuel effeciency and power level. If I could have upped budget to £25k I could manage an XF 3.0D, but it's 20% down on power, and while it's only £5k more than a 535d the TCO impact is much larger, as it's a newer car and in a steeper section of the depreciation curve and general residuals are weaker. The Audi and Merc offerings are not even worth considering.