The only people who can say if a pool is salt ready or not without voiding a warranty is the manufacturer, if they state yes then great but you want it in writing. From the little bit of research I did the difference seems to be resin bottom track, top rails and uprights with a steel walled pool or a complete resin pool makes it salt ready. When I was shopping for this pool I went to 2 stores 1 had no salt ready pools and the one we bought from did have salt ready pools. We did not buy it because of the salt but because they gave us a better price for the pool package we wanted. I don't think salt water contributed to your liner failure but maybe the rust on the wall did. Our liner lasted 20 years and just ripped under the water line one day for no reason, we were lucky to get that long from the liner.
Hard plumb! our last pool had the AG hoses and they gave me issues all the time, hard plumbing never entered my mind. I would come home from work or wake up and see my hose acting like a fountain. Had a hose pop off once or twice as well. Cutting PVC pipe is easy, I'm sure plenty of YouTube videos on how to do it. Just make sure that you have unions and shutoffs on the pipes to make taking it apart if need be easy. I suggest shutoffs by the pool on the skimmer and return, some have suggested shutoffs at both the pool and the filter. Speaking of the filter don't forget unions at the filter to the pump if that gets hard plumbed.
You mentioned liquid chlorine, I ran our last pool mostly on bleach and it worked out fine. I did have a chlorinator for when we went on vacation. This is our first year with this pool and I went with a SWG for "ease of use" but bought 4 gallons of liquid chlorine in May for startup and haven't turned the SWG on yet as I just opened my last jug last weekend. Other than having gallons of bleach (it was very cheap a few years ago) hanging around, using it wasn't a big deal but this is just my opinion.