For aspiring thfs..
Snowslit : Acc or Att, or both. Can go as high as 22, possibly higher.
Leafslit: TA or DW.
Duskslit: Crit Dmg/WSD.
Dusktip: STR/DEX.
* All of these stones have other augments, but these are the main thf relevant ones.
Also note that with TA2 Augment, Felistris Mask is unfortunately out of a spot.