[dBlast]

With a chip, don't you have to update it or reflash it everytime you add a performance mod in order to optimize its capabilities. (i.e. going to the shop for a retune or mail back and fore) Therefore it would be best to get a chip after all of your foreseeable performance mods.

With a flasher, would you be conceivably be able to do this yourself?

I, like Andrew, have pretty much most of the NA bolts-ons as well. My next mods in order would be:
SVT Header conversion kit, with high flow cat and flex (keep it legal)
Cams and cam gears
Chip with hopefully a dyno tune.