Electrically heated salt baths are common in industry, and I used and electric kiln unit for several years as my high temp salt bath. However, after using that method for years and then switching to a gas fired arrangement I would never go back. There is no way to keep even the best stainless steel tube leak proof indefinitely to avoid endless and VERY costly problems. The slightest infiltration of salt into the kiln interior will spell disaster. No element can come in contact with salts and then survive the slightest heating and, worst of all, the soft refractory lining is like a sponge to salts, it will soak it up and diffuse it throughout the entire material until every part of your elements are exposed to the salt. So even if you install brand new elements, they are doomed as soon as you fire the kiln until you replace all of the refractory lining as well. Salt infiltration can result from accidental dripping in dragout, pinhole leaks, popping and scattering of solid salts as they heat, and popping and splattering of liquid salts in use. Perhaps the most exhilarating side effect of salt entering the kiln chamber is that they are interestingly conductive, so the first sign that you have a pinhole leak will be your work giving your hand some voltage as the vaporized salts contact the elements.
Putting high temp in my kilns probably cost me three times the price of my kilns due to the endless repairs. I still use electric kilns for low temp, salt bath heating, but they are a different beast entirely. I have been working with salts longer than most and switched to gas high temp units almost 15 years ago and have never regretted it. I believe others avoiding the high temp in a kiln would be a decision that they would not regret.