I'm not entirely sure it's doable with the current system or not, but with the larger group queues like Coil, CT and Frontlines, it's a real issue with people declining time and time again.

Tell me if I'm wrong, but does it wipe the entire group makeup in the queue when someone declines and make you wait for an entire new group?

If this is the case, wouldn't it make more sense to keep that partially formed group together in the queue instead of breaking it down and solo queuing all of them again? I notice when someone declines, I end up with 0/0/(me) weather I'm dps, tank or healer, and then the group begins to reform. If this is how it actually works, it should be adjusted to keep the partially made group together, and just fill the slots, because those that already accepted are obviously ready at that point. (Though that's not necessarily the case, because that just pools you solo'ly with everyone else in that position for an entirely new group to be reformed if possible)