I would definitely agree that when buying used, the small additional outlay for a higher spec model is greatly beneficial in both personal enjoyment whilst using the car, but also greatly assists in the subsequent sale of the car. Many features you may never use, but if they have been mainly paid for by the first owner, then the benefits from having them can't be understated.
I have always bought the highest spec I can - Ghia models when I had Fords, CD / CDX models with Cavaliers, and over the last 15 years, Elite models with Omegas. My wife wanted a Honda CRV so we got an EX auto; the old one sold fast because it had extras over and above normal EX models.
I also have an SUV which has a 7 seat option with the top spec models amongst other features. When looking around, I considered the 5 seat version as it was considerably cheaper but decided to go for the top spec version. I'm now glad I did as it appears that the 5 seat versions don't sell well in the used car market and take a long time to sell whereas the 7 seat versions sell. In the MY 15, options were added such as power tail gate with ' hands full' feature, side blinds, heated rear seats, compass, memory seats, lane assist, so it was important that I got a late 15 model rather than early as these options, whilst they didn't particularly affect the purchase price, make it better vehicle to have, but are good selling points when advertising it when the time comes.