Why not alternate ilvls between crafted and dropped gear? As an example, iLVL60 crafted, iLVL 70 dropped/tome purchase, iLVL 80 crafted, ilvl90 dropped/tome purchase etc this might give a good enough gap, forcing people to purchase some gear to attempt the next level dungeon?, and perhaps after a big patch or 2 have said missing slots filled (by offerring craftable alternatives to iLVL gear that is droppable, and droppable gear for previously non droppable iLVL), and always having the highest/best gear be droppable/tome purchase, but at the same time requiring at least a few iLVL gears from the lower tear (craftable) to increase the proficiency of the player while working on getting the best gear from the hardest dungeon, while also not making it a must have requirement to attempt the highest dungeon as to not force people to feel pressured to purchase the best gear.