The best peanut butter, in my subjective opinion, contains peanuts and nothing else. Liquidize the nuts in a food processor until it's as smooth as you want it; and you're done.
Peanut butter made this way might go a bit stiff if you leave it, but give it a good stir and it'll go back to normal.
Good wholefood brands sell ready-made peanut butter of this kind, with only peanuts on the ingredients list.
In your recipe:
- Salt and honey are added for flavour
- Peanut oil is added to make the consistency thinner
If you like those flavours, then by all means add salt and honey.
Kosher salt comes in flakes or large grains. If you add it late, or don't process the mixture for long, then there will be grains of salt in the mixture; you may like this. I'm fairly sure that since peanuts are oily, not watery, it's possible for grains of salt to remain in there a long time without dissolving.
If you use table salt -- or if you use kosher salt and process for a long time -- the salt will fully dissolve and its flavour will be evenly spread through the mixture.