I don't really understand what the point is, TA already lined up with the other buffs...
We don't really know yet what the changes will fully be, if Mug still is the Ninki boost tho then our opener will be weird...
They may as well just remove the Ninki cost on Bunshin then.

Mug also just feels weird thematically as the damage buff, at least rename it Armor Crush and rename Armor Crush to something else.
Armor Crush doesn't make sense for a Huiton extension either.

And I also hope the damage buff won't be just 5%...
NIN being support DPS with a frequent damage buff was one of my favorite things about NIN.
Just making it a 5% 120s damage buff will homogenize it and just make it no different than the rest.

Edit: If they really wanted to fix something then I mean, Doton as part of your opener is the clunky stuff that remains imo.
Especially on some fights and if you're a PF warrior, what other Job has to deal with that in their opener?