Is Minfilia always useless ?

[Brightamethyst]

1. We never see her actually doing anything that she supposedly does. Negotiations etc.
-Tataru does all the paperwork, finance, setting up meetings with everyone and being the point of contact
-Alphinaud does most of the negotiation work on camera, which is very important to the telling of the story. Show dont say

They only seriously took on those roles after Minfilia was gone.

Tataru is the office manager. She's in charge of internal things like keeping everyone supplied and making sure the Rising Stones rent gets paid. Even now most of her dealings and negotiations are about how best to support the Scions themselves. She's making deals with merchants and support staff, not nation leaders.

Alphinaud didn't become the professional diplomat he is today until HW and SB. He started on that path in ARR (with disastrous results) but really only come into his own later on.