When low pop server's sage world battle problem gets solved, I'll start supporting this.

We (I'm in an active server too) get sage and less GNW reward per person
They get no sage but have more GNW reward per person.
I see that as a twisted "two wrong make a right" sort of fair.

On the note of large winning group vs small losing group in an active server, there are other benefits to having a large group. higher group skill, more activity packs per week (good luck having a group of a dozen or so active player finishing those), and chances are, better plunder/convoy results. So don't just tunnel vision on the one thing.