They undid the buff in the second hotfix today because it was crashing games. It will be back in december for the 1999 update. I didn't get to play with the buffed koumei, but what they changed was that kill assists counted towards your 2. On paper it makes her way less frustrating to play in squads, since you don't have to compete with your braindead team who are just using aoe weapons to explode the whole room while you are trying to set up to do the challenge. She's still pretty good in solo, endurace type missions because being able to stack decrees is broken.