Apparently new heads, (big maybe)crankshaft, pistons, turbine, fuel delivery system, camshafts, etc for spec 3.0(hopefully sorts out the vibration problems, although it already got a lot better through new MGU-H, and mapping). The rest is just tweaks to the intake, exhaust, fuel delivery and mapping. I'm guessing fuel injector upgrade is possible in the mean time, there's always scope to improve fuel delivery.
The height of cultivation is really nothing special. It is merely simplicity; the ability to express the utmost with the minimum. Mr.Lee