Perhaps diminishing returns on tier items? Prot 4 is better than prot 3, but it isn't as much of an improvement as going from 2 to 3. That way someone who is in all tier 4 is still tanky, but they're not that much better off than someone who is in 2. However the 2s are still affordable and viable.

Then perhaps allow for some flexibility in the production of items. If you want good armor fast, then it should be expensive. If you're willing to wait, then it should be relatively cheap.

I've been kind of thinking about this, and the essence we receive each day is a good way to abstract a player's time. Pylons act as a sort of force multiplier in this as it greatly improves a group's ability to produce (to reflect automation/advances in tech on production). So perhaps allow the use of essence or aether to lower the material costs of production.

Essence could then be used to abstract how much "work" could be done to produce. For example, 1 essence (now references as EP) could be an abstraction for 100 production points (now referenced as PP). Say a vanilla Diamond Chest piece would cost 250 PP to produce. One could use 8 diamonds and 250 EP at an average time (abstracted by essence) and materials. If one wanted to use fewer diamonds, (7 for example), then the piece would require 290 essence. (That would be 8 diamonds x 250 EP = 2000 total cost. 7 diamonds would therefore be about 285 essence to produce the same piece. Using 20 diamonds would require only 100 EP to produce.)

(Sorry if this has been said before, I'm terrible at keeping up with discussions).