I found some missing instances in the base package. The instances below are almost unique by parametricity.

Data.Complex:

instance Functor Complex

instance Applicative Complex

instance Foldable Complex -- real first

instance Traversable Complex

Data.Functor.Identity:

instance Monoid a => Monoid (Identity a)

Control.Applicative:

instance Foldable ZipList

instance Traversable ZipList

I'm going to write a patch if there is no issue with them.

Also, I wonder if () could be Storable:

instance Storable () where

sizeOf _ = 0

alignment _ = 1

peek _ = return ()

poke _ _ = return ()