I believe that by the time he can kill Ultimates without support, the player will likely have a full grid anyways. So working towards unlocking Soul Weapons seems like the natural evolution of Disaster Farming.
Didn't know Standard Raid was more efficient for weapon farming. Is it the case for Eidolon drops as well? But it seems to me Ultimate drops only Assault weapons, whereas the lesser Raids can drop Defenders as well.
I try to have all the frames covered as well. I just was inspired to come up with more defensive approaches after seeing your take on Guild Orders. You used, for example, 2 Ignited Dragoons and a Nova Kaiser Dragoon against Icarus, in order to always have Wind Resistance Up. Inspired by that, I came up with the strategy of always having Defense Up, as it would mean less resources spent (2 hime slots against 3 Eidolons slots. The Eidolons could be better stat sticks, for example).
Raising Defense right before an Overdrive is coming seemed risky, Icarus seems to nuke out of nowhere sometimes.