just going to throw this out there, by making overworld NMs not be claim based, they can, if executed properly actually make the overworld much more engaging then it is now, and than it was in ffxi. A great epic battle that anyone can contribute too, is over all a more entertaining system, and is more likely to make people enjoy the overworld more. Imagine you walk over and see king behemoth attacking a settlement, 6 people are fighting him, imagine you can actually jump in and get credit.
Imagine the type of mechanics you can develop for, when you know everyone can join in. They mentioned monsters summoning other monsters depending on how the people they are fighting are.

Imagine now, that this, king behemoth was attacking the settlement, suddenly 21 people join in to try to smash him. Oh man he was easy mode with 30 people. but right as he dies he summons god behemoth who only comes out if 35 or more people of certain levels was attacking KB.

there is a great amount of very good and interesting possibilities to a games overworld without a rigid claiming system, and you will, and may have already seen peices of this in other games. Whether they execute it well is one story, but in and of itself a no claim system is not inherently evil.

And if they do some type of best player gets drop boost or something similar, you will actually be competing while at the same time working together. There is many ways to go about this. you should probably give suggestions on how to implement some of these things, and hope that they listen