Also to keep this on thread Welcome.
I used to have an S2000 and I much prefer my Z, its much more progrssive and not so much all or nothing.
Mod wize, unless your going FI, go for Plenum, HF cats and some CI. You can get an ECU remap done these days instead of a piggy back ecu, if you do this then you may as well get your zorst done too. I would also recommend getting yyour brakes and sus upgraded