Given the context I’m not sure I understand. Like I said earlier, “If you want say, Slaughterer IV, you have to unlock tiers I - III first.” But it may be more than that like needing to unlock X blessings per tier first before getting access to the next tier, etc. I based my guess on this quote:
Either way, you can’t jump directly to Tier 4 blessings. You move through the lower tiers first.
If you’re talking about the migration however, we don’t know any specifics about the currency exchange. But for a whole lot of reasons I think it’s very likely something like ‘blessing’ x ‘tier’ = ‘Mastery xp’. So Slaughterer IV will be worth more than III, nvm I. Either way, I’m sure all blessing tiers will have value so you should unlock them if you can. How much value, and whether it’s worth wasting money nvm. materials to farm them? That’s another question entirely. The stores are super cheap tho so spending the 10k or whatever for blues & checking Melk’s for blessings you don’t have yet is probably a good idea.