Expectations can be adjusted to suit the students, the teachers, and the ambitions of the implanted curriculum sequence.
With a minimal perturbation to existing practice, symmetry could be complementary to existing descriptions. Students might be expected to account for regularities using the idea of symmetry, and perhaps of symmetry breaking.
More ambitious sequences could be developed, implying a more fundamental rethink of physics sequencing, and opening up further avenues of development, for example dualities and gauge symmetries. Here the challenge in working these into a curriculum is to work up and trial manipulable models, going beyond the many analogies already developed.