Campaigns - how to prevent a landslide?

[Alcyon]

This doesn't necessarily address your issue, but we're lucky enough to have 26 people in our crusade campaign online, so we're running brackets. Every 3 games you get paired into a group of 6 or so players with similar amounts of total VP, and you're only paired against those players. This way you only really face people with similar amounts of XP or army power level generally, and you can aim for a particular bracket if you know the average power of your force relative to the meta.

 

Ultimately I think you should either run a competitive tournament or a narrative campaign. You can do a little of each but ultimately it'll mostly be one or the other.