Not to muddy the waters here, but is there a different way thats already in use? For example, most suppressors today have a proprietary type of FH/MB and that’s how they are mounted to the gun. Why not take a FH/MB and permanently attach to a Uzi barrel nut (or threaded barrel). Then you have a muzzle device and a quick attach point for a suppressor. I have an Octane 9 and I can use direct thread or an Alpha ASR mount. I am sure there are cons to this, but other methods have cons too.
Sure you can use an ASR mount or a Griffin EZ lok mount which is gaining popularity.
My personal preference again is the native UZI barrel nut mount designed to be used with a cut down UZI barrel as the most compact setup compared to anything else and I also think the best looking.
I personally like the 3 lug second since I also have an MP5 and have standardized on 3 lug for my 9mm M16 builds as well.
Another reason is 3 lug has been around for what over 30 years now and today there are several quality sources for the adatpers to screw on the barrel and thread the way I have discussed many times to match the full length of the adapter.
My preferred Bixler mount is also more solid and robust than the push / turn 3 lug mounts and also over 30 years old with expired patents and now made by Shaw Armament and now Hansohn Brothers will be making them at the end of the year as well. Not to mention they are not that complicated and I made my own as well.
So this is more of an 'open source' approach and no worries of company X,Y,Z not making the adapters and hopefully more people making the Bixler mounts but if you like the wobbly push / turn mount, there are MANY choices for those w/ no concerns of being locked into a particular vendor.
Contrast that with the amount of sources for XYZ proprietary mounts...many times only 1 source.