The original poster asked about Shok-Buff and heavier springs, and asked about other things he could do to extend frame life. I am a wordsmith, not a gunsmith. I have shot several 92 and 96 pistols extensively. Most of them are surplused Police pistols. I have tried Shok-Buffs in several 9mm and .40 pistols, and it caused jamming in some 9mm and some .40 pistols. I use them in 90-series pistols they do not cause jams in. After quite a few thousand rounds through a 96G Centurion that had been shot a lot when it came to me, no problems with the frame, but the extractor did break.
Beretta recommends the same spring weight in 9mm and .40 pistols, 13 pounds IIRC. Someone recommended I try the next weight up in the .40, 14 pounds, and I did so. No jams or other functioning problems. I changed all of my 96 pistols to 14 pound Wolff springs.
Something I would worry more about is the locking block. Beretta has used several designs in an attempt to prolong the life of the locking block. When the locking block fails, it may damage the frame. Early design locking blocks sometimes broke rather quickly, some times not after long use. Inspect the block regularly, and if you see a crack forming at the root of one of the wings, change the block. If you have an early design block, change it for a late design. I believe the US Military design life of the block is 20,000 rounds.
One hears a lot more people worry about cracks forming in the slide on 90 series pistols. I've not had a 90 series pistol slide crack. I've not seen a 90 series pistol whose slide had cracked. The 92 design was derived from the Walther P38, and I have cracked a P38 slide, after 25 years of being regularly shot with WWII surplus submachine gun ammo.