The other logical use would be for missile launchers, I suppose. I would think pretty hard about reducing any TN mineral overall though, especially as missiles are essentially consumables, which drains Tritanium from the game overall (your specific experience in general or in a given game may vary, but across all games it should represent something of a limiting factor).
Although it's not a short term solution, some sort of transmutation tech would be a partial answer to mineral supply/demand problems, although any such tech should be pretty limited in its' usefulness, even at high tech levels, so as to not trivialise the mining aspect of the economy. Perhaps a large building with high worker requirements (to restrict deployment of such buildings), and abysmal conversion efficiency (say 200:1 at T1, dropping to 10:1 at max tech, or something).