Agree with most of this. In design I believe they initially benchmarked the S2000 for the ideal shift but then realised that they wanted to have a much higher level of driveablity - so wanted an engine with much more torque at much lower revs - hence the need for a somewhat beefier box and operation - I personally think you do adapt to it over time - there is a bit of a knack to it.
The one thing I would add is, given the current UK road surfaces, I would regard the balance between handling and ride quality of the 350Z to be very good. I think this is a very important factor to achieving road performance in the real world.