I am pretty surprised to hear that you found the car that uncomfortable. Then I realized you have larger wheels and what appears to be lower and I'm sure stiffer suspension. What suspension is on the car? I am planning to roll on stock suspension and wheels for such a long trip.
That may have something to do with it, yeah. The wheels are 17/18 and the suspension is Eibach springs over Bilstein shocks. I think the ride is about comparable to my Legend (it is between my medium and hard settings) though. I think there is also significantly less space in the NSX in general: I can't move my feet about in the wheel well (the dead pedal is tiny and it's hard to stretch against, for example) and my g/f can't lean her seat waaaay back and sleep.
I mean, these were expected issues when I purchased the car and I'm not coming in here complaining like the NSX is unsuitable for road trips. It is just a very different type of car from anything I've ever previously taken on long trips and it'll be something we have to adjust to.