Replica Genji Armor sets.

[Vahlnir]

Actually, with a properly designed log it would most likely take even less space than the inventory expansion we got. With the log there is no longer a reason to keep the actual item id, but rather just use one bit to declare if the item is unlocked or not which is nothing compared to an inventory slot that needs to manage item id, glamour id, dye id, durability and quantity all of which require multiple bits. Then there is the fact that most armor sets comes in pairs of 5 and accessories in pairs of 4, so we can cut it down even further by making it a requirement to have the entire set before it is unlocked in the log. And want to go even more extreme, they could require all the items in an entire tier which would divide requirement even more.

Looking at armors there are about 1800 pieces of gloves/legs/feet and 2000 for chest/helm, so it's safe to assume that the total of full armor sets is about 1800. One bit for each 5 piece set would be a total of 214 byte, that's about the 1/4 of byte needed for this text which isn't exactly much.

I think part of what is holding SE back (probably a big part) is that they are afraid that people won't pay for extra retainers. They most certainly still would. Maybe a few less, but I think the drop would be negligible at best. They are worth keeping around just for ventures alone.