Personally I don't think these limited event items should get adjusted. Isn't that the point of having an event? Having cool new items to look forward to. And on top of that there just doesn't seem like a good enough reason to change them. If players get demotivated because their high damage they had during the event disappears, that's just tough. Every player should know that these event items will expire eventually and the event will end. In my opinion players losing motivation shouldn't alter what comes in these "GMS like" events. Everyone eventually loses motivation, lets be real. I currently feel like the items are acceptable because I know they're going to go away eventually so what's to care for. And once the items are gone, its just back to the same old Phoenix from before. There's only so many events that take place.
Pirates releasing at the same time as Christmas does make it very convenient for them. I don't really have any opinion on that.
I'm also not aware of any future events that will have items to this extent. Not opposed to change just my thoughts.