Well, it all depends on how textures are shared and whether body geometry is rendered underneath the outfit. If the textures for an outfit are unique (or at least nearly unique), and the outfit renders skin geometry beneath it (like with the miner shirt/vest initially selected for this mod), then they can be swapped to the swimsuits fairly easily (or other costume pieces). If the textures are shared with other outfit pieces, then when you do the texture swap all outfits using that texture are affected.
Of course you also have to consider how easy it is to acquire the outfit. The Beachcomber outfit now can only be obtained off the Exchange, and may be very expensive, whereas the Miner outfits are available for a modest dilithium and fleet credit cost from any T3 fleet dil mine -- and even if you're not in a fleet you can still buy it by being invited to a T3 dil mine.
Still, if you (and/or others) would like the Beachcomber parts swapped to swimsuits, I'll investigate and see if it is possible (as well as work on fixing the Trill spots for the existing mod).