in my API, this would be obtained with the already existing values method instead of fieldvalues.
in newest version of AbstractTensors there is a simplified variant of StaticVector implemented
which loads much faster than StaticArrays and provides all the basic features needed for Values.
AbstractTensors.Values # simplified SVector variant
AbstractTensors.values # alternative to fieldvalues
my proposal is using simple Values and values for internal values of TensorAlgebra