So I have a bit of news to report concerning the Alps SKCM (tactile) Green switch in relation to Alps SKCM Brown:
I finally tried doing some spring swaps, and I took a linear green spring, the lightest from the complicated Alps family, and swapped it into the SKCM Green housing.
Unfortunately, much like the SKCM Brown, the actuation force was not significantly reduced.
Note that this was done with pine SKCM Green, which is very similar to SKCM Brown.
• SKCM Browns were around 75 g to bottom out, 80g to consistently bottom out.
• SKCM Greens were around 70 g to bottom out, and 75g to consistently bottom out.
• SKCM Brown and pine SKCM Green have the same consistent bottom out force, at 80g. Retested to be sure. 75g gets them down at times, and even 70g for Greens, but 80g always gets them both down.
• With the SKCL Green spring, which is around 50g, the total force to bottom out the SKCM Green switch was not reduced.
With that said, I think that it's the leaf shape itself that makes the weight stiffer. Like SKCM Brown, lighter springs had no real effect.