I am curious as to the specifics of the mods you are intending.
I bought one decades ago when the things were new. Replaced a constantly jamming stainless Bauer with it. I carried it as a second gun, backing up a .38 Special. Was initially happy. Mine was/is the Teflon black model. Over the years all of the Teflon has flaked away. I have shot mine a lot. I used to keep it loaded with the early CCI Stingers (I had about 700 rounds of that first lot of scary Stingers). Used Hornet & Viper ammo for plinking (occasional boring 40 grain solids too). I had 3 magazines for it. [Down to 2 now.] I would say it was about 95% reliable. Mostly feed errors. Initially blamed the mag, so I bought a second one, then tried a third. No difference. Could run it slow fire all day, but rapid fire was bang,bang,bang,click. In slow fire I could X ring the old Colt targets all day at 21 feet which was all I wanted anyway.
I never had any sense of impending blowup. That could happen I guess with a blocked barrel and no maintenance, but wasn't (isn't) viewed as the issue that retired it.
Two separate events resulted in the retirement of my J-22.
Event 1. I spent a day in the woods with it. The gun was in my field jacket pocket (I could carry concealed back then) all day. I fired some shots with it at tin cans till it was empty. Later I went home. I reloaded the magazine, inserted it and racked the slide. BOOM in the bedroom and the gun falls out of my hand. NO, my finger was not on the trigger. Small hole in the room wall, stopped by a brick outer wall. Nothing else (beyond a ringing in my ears). Lucky. What the H just happened? Slide was locked back in a classic stovepipe. Not surprising since I didn't have a shooting grip on it when it unexpectedly discharged. I removed the clip and carefully began the exam. I found the shell casing and started there. Not a firing pin indent, more of a crush mark, clue 1. I found the cause and it was an eye opener because many other pistols have a similar design vulnerability. The extractor was jammed in the downmost position by what looked like a very tiny sliver of bark (pocket lint from a day in the woods.) During the reload the slide went forward, the extractor hit the new cartridge rim, but because the sliver of wood had somehow worked in beneath it, did NOT move out of the way like it was supposed to. Instead the extractor crushed the rim, Boom. I have had paranoia about external extractors on rim fires ever since.
Incident 2 a year later. At the end of the day the gun is examined and the left grip is broken in two. Upon removal of the top half of the grip, the safety bar, the ball bearing, and the spring fall off. There was no Internet in that time. Netscape Gold was years away, so was Yahoo. This meant until I got new grips the gun had no safety. I hadn't heard of Jack First in those days, so that was that.
I replaced the J22 with a Colt 380, later replaced that with a Mustang. About a decade later I finally got one of the newer Jennings grip sets. They fit, but my J-22 now sits in it's tattered little blue box in one of the safes. I think it had about a decade of carry and maybe 1400 practice rounds put through it.
I am very curious to learn if any of your intended mods will address the inability of the factory magazines to keep up with rapid fire.