Here's how I did a quick and easy fix to prevent bolt stop breakage in my Colt style 9mm.
I got the spacers below from Lowe's for about $1.85 for a pack of 2. (These in the pic have been modified already)
Since they are 1" outside they need to be trimmed down just a bit.
I found that the sanding mandrel (picture insert) for my Dremel fit perfectly in the hole without a sanding drum in place. I installed the spacer on the drum and snugged it up.
I then ran it at a moderate speed (so as not to explode my Dremel) on a piece of coarse emery cloth until it would just slide on it's own into the buffer tube.
I dropped in 2 of them, then put in the spring on top of them, then the standard RRA 9mm buffer and checked it. Low and behold the bolt has right about 1/8 inch of travel to the bolt stop when fully rearward.
I ran 200 rounds through it yesterday with much of that bump fired and had zero issues.
PS- The ProMags kept up with bump firing just fine.



Here's a link to the video of the rifle running with a ProMag I cut down to 20 rounds.
(This was the first time I've attempted bump firing. Yes I know it is useless, but it was fun to try and it was a good test for the gear. And all rounds were kept in the lower half of the berm)
Edit to add: Ammo used was WWB 115gr.

Video Link

deleted by me

Update.....
This is still working, but it has left a bit of indent on the plastic tailpiece of my buffer.
It's purely cosmetic, but it is a bit ugly after 800 rounds.

Try $1.75 in coins (quarters) placed in the buffer tube.  Worked for me, took about 1 min of time, and still fully functional after about 10,000 rounds.

I like your idea though.