Newer Diesels...

[1616six]

BMW 116d in the comfiest spec with the smallest tyres you can find?

Or an old shape Hyundai i30 (like 12 plate or older) although the gearboxes and dmfs go on the Hyundai sometimes in less than 10k if abused.

116d is painfully slow. I was gonna say 120d, the older ones can occasionally have swirl flap issues but it's not hard to get the £50 odd kit to fix them open.