It may be useful to fix the grail event if you are planning on running it again.
In this one, both sides were trying to lose the first part, since the rewards of losing and fighting off the waves seems to be MUCH higher than winning and getting a few purple items. The resources stolen sure do not help. Im a high contributer, and Ive only made about 3 hours of production. You can buy those resources with a few winning waves of gold for the losing side.
And if you are trying to say the main advantage would be the chance to gain territory, then forget it since the winner has absolutely no chance of winning that. Maybe if there was at least 3X the mercs, there would be a chance of that