IMO, I think that Shadowbringers Relics made a decent attempt at balancing "Upfront grind for a single relic" and "Easier grind for additional relics" and it would definitely be cool if that design philosophy made it into other relic grinds, but I definitely wouldn't expect that to happen. I think that a combination of their solutions were the best way of handling it:

1. One time steps that are skipped for future relics
2. Content overlap whenever working on relics on different steps (i.e. the same content gives you items for Steps 2 and 5 meaning you're working on 2 relics at once)

Also, technically related was making more items drop as the content aged, it might be nice to bake that into running multiple relics as well (e.g. DR drops went from 3 per run to 5 per run IIRC?) would be nice if the first relic would take 15 and the second+ would take 9 for example.



I honestly think that additional relic grind only really matters to a small number of people so lessening the grind won't really affect many people, but it will make those people happy.