As others have echoed here, there is a severe disparity between the amount of attention Frontlines gets, in the form of mechanical changes, rewards and ease of access versus that of Rival Wings.

The fact that NA/EU has to resort to out-of-game coordination to even have a remote possibility of the gamemode being available is pretty damning. Especially on Data Centres which don't house a particularly active population, PvP or otherwise. We need serious developer intevention to ensure this content continues to be in use.

Add Rival Wings either to the Roulette or bunded into the Frontlines roulette.
More rewards.
Greater ease-of-access for new comers.
Possibly look at reducing the numbers required to pop the queue, although this could severly change the power dynamic of the mode.