I keep hearing from everyone I chat with about this game that sortie is an absolutely terrible grind which they loathe.
Please rebuild it.
When only the upstairs existed, it was still interesting. You could push to get every box & NM in the zone.
Once you added the basement (EFGH) that was no where even close to possible anymore. It effectively ruined the hard work you put into the event.
When Aminon was added it got even worse since the only way to get GOOD points each run is to push for 9 bosses or as close to that as possible every run.
I suggest breaking the event up into multiple parts.
Take a page from Incursion & Vagary.
Killing Aminon resets the zone, destroying all temp items and leveling up sortie just like Grrk-Frut the Charlatan does for incursion. After reaching the highest sortie level, instead killing Aminon 100% drops a Mesosiderite and the zone's level resets to the lowest level. On the highest level sortie, the NMs are enraged like how they were after releasing primes.
The sortie level can also act as a multiplier for gallimaufry.
Instead of requiring everyone to own a prime weapon on a specific stage for -ites, each level drops ONLY a single type of {Eikondrite,Octahedrite,Hexahedrite,Mesosiderite}. As such the highest level with enraged bosses would drop none of them aside from Aminon.
Other changes I would suggest are to change the old cases. Create an Old Case +2. Instead of old case rarely granting ??? earring+1's, change that to occasionally granting an Old Case +1. Same thing for Old Case +1 & ??? Earring+2's.
Along with the change to Old Cases, I suggest a change to ??? Earrings. Remove the [Exclusive] tag on them. Let us trade them and bazaar them. It will greatly incentivize players to do the event.
Players who don't need any more prime weapons or empyrean gear upgrades could continue spending gallimaufry on old cases praying for the double upgrade to an Old Case +2. Players who get the wrong earring could trade with someone who has the earring they desire.
Another possible addition would be to completely remove the floor lockout on rewards while increasing party size from 6 to 18. This way more can enjoy the event at the same time and the group can split off complete their own tasks while still getting the full benefits of the group: even if you are assigned to one of the less rewarding tasks.