The base is lapped down to 600-grit sandpaper. It only looks scratched because you can see your reflection in it, and 600-grit paper always leaves marks. If you want a "mirror", lap it with 1200, then with 2000, then follow up with Brasso and a cloth, and then a jeweller's rouge. The "scratches" you're referring to are in the order of less than 0.1 micron deep. In my own testing, stopping at 600-grit always seemed to yield better results, as in it's better for it to be very lightly scratched. So it's like the way it is on purpose.
The centre nozzle is the way it is on purpose. I won't go into the gory details here, but it's like that for a reason.
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