I don't wanna jump to conclusions but I feel that the non boss strata's are rather useless at the moment. You earn less crowns and the rewards aren't as good as the boss strata's
This is especially the case with tier 3. I always find no party in non vanaduke strata's which makes sense.
If it is the case of them being useless. How could 3 rings make them more apealing?
You would be right in saying that. There isn't much incentive. It feels like it is partially by design.