Just to be clear, a salt water pool is chlorine. The salt water chlorine generator turns the dissolved salt into sodium hypochlorite. Sodium hypochlorite is the main ingredient in chlorine bleach.
We've had an above ground pool for about 20 years.
We started with a normal chlorine pool. Our oldest child developed a reaction to chlorine. We switched to Baquacil for about 10 years. It worked fine, but was expensive and prone to algae problems a couple times a year, and the water had a metallic taste.
Kid got less sensitive to chlorine, and we switched to a salt water pool for about 8 years, using a cheap salt water chlorine generator. Works great (until it died last year). We are back to just adding a jug of 10% sodium hypochlorite when the numbers drop, and 2 oz of algaecide once a week.
To answer your questions about salt and corrosion, YES! Cheap stainless steel bolts will corrode lightly. Steel bolts under pool caps, hose clamps, metal hardware on steps/ladders, etc... can get corroded from the salt. Even if they never get wet, they can get corroded. The pump will get corroded as well if it's not made for salt water. The metal rail under an above ground pool sidewalls will corrode. Metal sidewalls will corrode if the paint gets scratched. The areas around the skimmer pass-through and return line, which are not normally painted on the fine cut edge will corrode. Basically, anything metal that is not painted will corrode.
Hope that helps with some of your questions.