Yeah, Senna was heavily involved with the development of the NSX. The first one they produced was too flimsy, when he tested it he gave specific feedback about how it handled vs how he felt it should handle, and Honda then totally redesigned the chassis. He made it a car that was able to outhandle the more expensive Italian counterparts The NSX is pretty much the only car that was developed in conjunction with an F1 driver - suppose that's what made Honda so good throughout the 90's, they made good use of their top driver!! No other company has done this for a mass produced car AFAIK.
Shame about Senna really, he only ever wanted to drive for Honda, and unwillingly went to Renault - if he'd have stayed with the big H, who knows, he might not have been involved in that accident but the flip side of the coin is that sadly, someone of Senna's stature within the sport NEEDED to be killed in order for the sport and safety to progress....
Like Wayne Rainey in Moto GP (then 500cc) had to crash and cripple himself in order for safety to keep up - spine protectors and camel humps with built in protection would never ave developed without his accident. Sad but true...