The concept of popping off the insert in the event the ball is lest or damaged sounds like a good one. But, my knife with the most hard flips to full lockup and closures does not have an insert, and still works perfectly. A Kizer.
I did have one knife develop a significant lock-rock. I thought, "great, here's my chance to see if an insert change out works". But instead, I was sent a complete new knife. Massdrop knife.
Then I had another knife that I damaged the detent ball. But on ZT's, the ball is not on the insert. It's on a very thin pillar milled into the lock Ti, and stands through a hole in the insert. In the process of attempting ball removal, I destroyed the pillar, and was required to purchase the entire lock side. But will say that when it comes to an effective locking device, ZT does it well. In dozens of ZT's, this is the first issue of this kind I've ever had....And it was all my fault.