I have a couple of comments.
-> Buy Manual. You buy a sports car to feel the road and learn to drive on it. Going AUTO seems like "Your planning to have Grandma drive the car to Church."
-> Buying the Sport, Touring packages come with a lot of basic extras that you can (if you want) remove and upgrade. But the fact is that they are there, you only have one chance to do this in most cases. If you go BASE, you can not add Navi, Sync Trans, Nissan Brakes, etc and may not even justify the value add.
I got the Sport, Touring, Navi, and believe me... The 370z kicks ***. I just replaced the exhaust with a Fast Intention and I could not be any happier. I'm spending my upfront money on items that will make me happy and increase the value.