If you only want the existing kernels, this makes sense. And in the long term it would be useful to have a library of common kernels for assembling FEM stiffnes

If you only want the existing kernels, this makes sense. And in the long term it would be useful to have a library of common kernels for assembling FEM stiffness and mass matrices for various kinds of commonly-used elements, etc. Compare to GSLS; the shading language is unnecessary if you only want to use a handful of pre-made shaders, but usually that is not case.