Sinvaders
You forget that all pieces don't need the same amount of mats. i.e recipe are differents for small and big pieces composing a set.
Then just have a BQ, MQ, and HQ set for each armor type, and have the material amount requirement be the total sum of what it would be if you crafted them separately.
I'd probably increase the crafting time for a set to be equal to crafting 4/5 (HA) pieces of gear; just makes sense to me since you're crafting.. well, a full set. lol
Doesn't need to be complicated.
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"To believe an ideal is to be willing to betray it." - Kreia