Whilst great on paper there needs to be more incentive to run dungeons multiple times for this to be useful. Currently the xp and loot from dungeons are negligible. Most people only run dungeons either for their first story clear or as part of a roulette for the bonus xp and tomestones. The majority wouldn't use this feature because after the first run the reward is much much smaller.

We would need to see much more useful loot and much better xp rewards for there to ever be a chance of having all four players actually want to run it again...