For your rust concern, the 3000-3500 ppm concentration in the actual water hasn't done any damage on my inground pool that I can tell, and it shouldn't. It's areas where you get splash out and dry up where the salt can accumulate and cause problems. On my inground the porous flagstone the builder put around the border is pretty torn up in the areas that get misted constantly around the water feature and skimmers - I'm confident that if it was something like brick that wouldn't happen. So, that's the deal on damage - yeah it will damage some stuff just like chlorine, water, and sunlight do.
On the maintenance side though, the heck you just went through? Day to day, I add half a gallon of acid to my pool a week. That's it. Chlorine is just a function of runtime of the pump (which enables the SWCG to produce), so that gets adjusted as the season ramps up and down. The pool can live like that for months - the salt water cell doesn't throw off CYA, everything's just stable.
I run it the lazy way until it's clear I need to SLAM, CC's up or I see a random black algae spot. Get everything including TA, CYA, Ph (to the low side), get borates back up, set the pump to run constantly at low flow, and then dump in 2.5gal of 12.5% from pinch-a-penny for $18 in there and just monitor the battle of SWCG vs Sun vs Algae vs CC until I feel like it's time to run a OCLT - shut the pump off, wait, test and see what's up. If it's all clean then I wash my DE filter out, recharge, keep chlorine a bit high for a few days via runtime and all is well.
So yeah, salt water is a huge shortcut for me and if I found myself with a new pool I wouldn't hesitate to add a cell. The economics with chlorine prices justify it on the face of it, and as far as the damage it causes that's going to be your own calculation. My other shortcut is borates, huge advocate of those but that's another story.