Since it's the chloride, not the metal, that makes a salt print work (by forming a silver halide when the silver nitrate is coated onto the salted paper), I don't see where you'd expect to see something different in a salt print made with barium chloride vs. one made with sodium chloride. If you want to make salt prints that are different, try a salt with a different halide (bromide, iodide, maybe even fluoride). My understanding is that you'd generally expect silver fluoride to be very, very slow and require very short UV, but silver iodide has been written up as "insensitive" to light (which seems odd, since I'd expect the weaker bond of a heavier halide to make the compound more sensitive and to longer wavelengths). Bromide is well known to be faster than chloride in applications like gelatin printing papers, however.