Overall I think it's a good set of gear (Except the Kenwood). Make sure you install those front speakers good, or you'll just get poo sound.

A custom box for the sub is always best, but the pre-fab ones work OK for the most part.

Only Pioneer head units worth getting are the PRS ones. The rest are too cheaply made.
Spend a few more $$ and get something that will last. Alpine CDE-117 or similar has plenty of tuning features and good quality sound.