The visual and aero changes include lightweight LMX6 aluminum wheels for around $450 each, as well as an add-on rear spoiler, front and rear bumpers and side skirts in the Aero Package (about $5,500 in fiberglass or $7,700 in wet carbon fiber). In addition, the $1,100 sports suspension kit incorporates reworked dampers and springs to improve handling while delivering a ride height that's lower by 30 millimeters.
The most interesting change, though, is the Sports Reset feature for roughly $1,400 US, which tunes the vehicle control module to both improve the driving characteristics that make it "possible to enjoy sports driving more" (according to Google Translate) and increase range. There are no official details on how many more miles can be tweaked out of the pack, but if any of these changes come to the US, this one would likely be the easiest to get people to sign up for.
For more JDM Leaf enhancements and pricing in yen, check out the translated Nismo release here.