to the OP, have you tried and confirmed that 295/30/19 will actually fit on an nsx?? im almost positive its too big, and it side wall may look too meaty.
however indeed if the sizes 225/40/18, 295/30/19 can be made to fit the nsx without issues (ie. downforce front fenders + remove front wheelwell liners, some minor fender rolling in the back) you will have a quite a long time to choose from all the good tires out there. these are common sizes amongst lexus is/3 series/c class/Porsche 997/certain amg models etc etc etc..