Some lovely colours. I find that these sort of shots often need “pumping up” a bit to recall the beauty of the sunset (slide film used to enrich and boost colours and contrast for us). Modern DSLRs are very accurate in their colour recording but can be subdued at the extremes of light. You have a fair few dust spots on your sensor by the look of it, were you closed right down? I usually try and keep the aperture around f8-11 for these sort of shots if possible.