Paragon, apotheosis, nonpareil, nonesuch are comparable when they mean a person or thing of consummate quality or transcendent excellence in its kind.
Paragon distinctively implies supremacy and incomparability.
Apotheosis basically applies to a raising from an earthly to a divine or ideal status, but it may be indistinguishable from paragon in denoting one that is the extreme and usually the highest of its kind.
Nonpareil and nonesuch, like paragon imply the absence of a rival or equal, but they sometimes impute uniqueness more strongly than excellence.