I would add a 28 pin DIP socket for the processor chip to the list. That would allow you to remove the chip and install it on a standard Arduino board for reprogramming, otherwise you will need to install ICSP pins or serial connections in your standalone construction. The odds are that some bugs will be discovered late in the project or new software functions will be desired or required, so don't assume that the chip will never have to be reprogrammed. It does take very little to build a standalone 168/329 chip to a project and frees up your Arduino board for further development on new projects.
Lefty