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Hmm, I didn't know that it was based on a specific place. I played FireRed a few years ago and just assumed the cave was frozen over because of the presence of Articuno and the other ice types.
If this is the place to ask, I have a suggestion.
Another hack called Pokémon PureRGB says that they found unused ice-looking tiles in the cave tileset, and used them for the Seafoam Island caves.
To me, this makes more sense to use instead of the brown rocky tiles that the other caves use...