I was thinking and for sam weapon If Kogarasumaru dramatically increased counter rate to say 50~75%[or higher if SE crazy since SE did make jumps forced crits] it would probably destroy every other gkt easily in tanking stuff, in term of damage due to counter procs, though if this is the case I get a feeling monks would be very very mad. So two other decent Options I could see happening which could be simply greatly improve the TE proc rate thus making it excellent for tanking like you mentioned, or maybe SE will let TE magically eat Spells and WSes that use to wipe or ignore TE that would be great too

though if something besides this I can't see it being that great at all.