Gathering overmelds are largely irrelevant though. Basic white 80 gear with grade 6 and no overmeld is plenty to gather ephemeral nodes and 2 star mats. The overmeld is just a QoL to bump yield up a little.
The best bet right now is to do the basic melds and spend all your custom deliveries on DoL. If you're a crafter, convert your accessories when they hit 100% and make new ones. This will let you accumulate materia gradually incase it matters in a later patch.