Do yourself a favor and skip the nature2. It adds metals (copper) to your pool which is weak at killing algae, doesn't kill bacteria at all. Also, it's really good at turning hair green. If you want some kind of automation to make care easier then a SWCG is a good choice if it doesn't void the warranty on your pool.

Also, 2hp sounds like it might be big time overkill for that size pool. I would go with a smaller pump and bigger filter.

As for the electrical question. Anything metal in or around your pool needs to be "bonded" which basically means connected together via a big copper wire. Don't skip this, it could be the difference between life and death literally. Then that line will probably get grounded. I'm sure the pool will come with instructions to this effect if you're doing everything yourself.