Likewise, these rewards are not what "sub casual" players like myself were looking for.
Coins, don't really care for 'em since Tomestone gear is 10x simplier to get.
Mettle? Not aiming for Savage so unless it's like 50k Mettle, not worth the stress/repairs.

Make it a separate queue like Delubrum is, and thus have autogroup set up.
If you're not going to set role requirements, at least have a lost actions cache in front of the instance. Yes, Lost Actions help, unfortunately the "tank" Lost Actions are a pain to get (Rank S mobs, grind random mobs endlessly for clusters, or spend gil on the MB and hope the appraisal gets you the Incense Lost Action since it shares the same "token" with 6 other actions).

Could say "This content isn't for players like you". Which is true. But still is the gateway to stage 4 of the relic weapon. So still probably want some folks like myself to repeat it.