The items I use or enjoy the most are:
Xenon headlamps with washer and self leveling
Mulit-function steering wheel
Heated seats (we have cold winters in Southern New England)
Space cloth seat covers (every time I auto-X and I don't slide out of my seat)
other items that might add to the resale:
17" wheels (too heavy for me, kept the stock 16")
Leather upholstery is very popular
Sun roof (also popular but very heavy)
Whatever you do you have to be happy with what you buy because you will have to live with it for at least a year. Buy what you like.