Thanks for asking and Dreamcar's comments are right on.
1) PASM? Adds a different dimension to the car, and comes standard on all high end Porsches for a reason. I never intend to track my Boxster and PASM is great for the streets as well. If you are concerned about the complexity & longevity of the suspension system, it is virtually bullet proof and the soft-top operation is more complex. As for 19" wheels requiring PASM, I am of the belief that the car still has an excellent ride with the standard suspension and 19" wheels, and if PASM is not in your budget, then you can still have a great car ownership experience with 18" or 19" wheels and no PASM.
2) Bi-Xenon? Necessary and should be standard.
3) BOSE or SoundPlus? If in your budget go for the BOSE, but you'll like the sound of the engine more.
4) Full leather? Go with PASM, Bi-Xenon and Bose before you opt for the full leather. I personally don't mind the plastic dash and those two mould marks runnning down the centre of the facia top. The leather dash has an added cut-out for the passenger airbag, which some find unappealing. If you can afford it, get the leather, but if prioritizing, go for the performance options.
In addition, I would suggest that you consider the Sport Chrono, which is one of my favorite options. Not only do I like the wart on the dashboard, but more importantly it puts the car in a hyper-gear, making the car respond quicker. If you are going for a manual shift, short-shift is an option that will not appear on the ordering website, as some believe the shift action is too hard, particularly when cold, but I must disagree, and would recommend it without hesitation. Lastly, for $250 go for the Sport Steering Wheel which just feels more substantial in your hands. My '06 had the standard wheel, which I thought was fine, but I now prefer the Sport Steering wheel on my '08, and could not go back to the larger/ thinner standard steering wheel. Ultimately, go for the performance options when prioritizing your options within a given budget.
vincesf