This is a little aside from the point, but may help anyway......
I'm not sure if your troubles are related to the zones you are LFG in or not. Most people try hunting Glowings assume that RSS is the best spot and bang their head on the wall trying to get groups there.
I dont know when the change was made, but it seems that MPG now drops a lot more glowing runes than it used to. I'm not sure what the situation on your sever is, but if it's like mine then MPG groups are a dime a dozen compared to RSS.