That’s interesting.
So the inconsistent feel of BOX Silent Brown comes from the springs. Makes sense.
I think you are supposed to use dedicated Kailh BOX springs for replacements, but I guess OUTEMU 68 G worked.
For a milder and quieter BOX Silent Brown, there’s also the Cookies & Cream mod:
Maybe the ideal BOX silent tactile for me would be Cookies & Cream, using aftermarket Kailh springs close to MX Brown [45/60 G].