Umm, I think all those numbers make it confusing? What about:
2A F ii LP ME (2a, fine, medium, low-po, med. elast) for me
And Dusa would be: 3A C iii HP LE
I'm still not sure about the elasticity one, but I already kind of think LP/HP in my head for the porosity. I think if its standardized for porosity and elasticity it will be easier to remember. So L=low, M=medium & H=high. Or should it be N=normal instead of medium?..