If you soften your water to 14 parts per million, that alone is enough to chew through water heaters rapidly. Softening adds salt to the water, which increases conductivity, which consumes anodes, which leads to heaters rusting out.
You probably don’t need to drain your tank because the softener took care of a lot of that. On the other hand, if you have aluminum anodes, you could still have a lot of sediment. But that would still only be a secondary issue.
The grounding issue is a good base to cover. I would ground the hot and cold lines. If I remember right, you bridge them with a piece of wire.
If you soften, you should make sure you don’t soften to zero parts per million. Fifty-100 is best. But you should definitely check the anode(s) frequently. Once every year or two if you change the softening to what I’ve suggested.
And finally, I’d suggest checking the water pressure. If it is over 80 psi, that could destroy heaters and piping, and thermal expansion could do the same. A water pressure gauge only costs $10. You can read up on these issues and how to use the gauge at Temperature/pressure Relief Valves in Tanklets, reachable from the link at the top of The Tank topics page.