I agree with the idea of making all of the materia of the same tier the same value. As it is we basically have tiers within materia tiers, corresponsing first to the title name, and then the value. Stacking could also be implemented at that point for even more inventory compaction. This also has the side effect of making materia easier to appraise, as the worth of a materia is only based off of the tier, and not an additional factor.