For the casual crafter, the crafting xp grind is enough of a deal. There should definitely be extra effort to make the best items, but I can't say I approve the method that was presented. You want to make it make sense? A +1 tome and (purified shard, or whatever is come up with next) makes.. a +1 exceptional stat bonus. Holy? Trade in a completed scarab (or three, if you want to demand a grind) from Necro 2 (which are sellable, tradable). Burst? Nec 3. Make things as demanding as wished, but also keep things simple. Having to do exaggerated efforts to make simple items only makes the whole thing seem too muddled and time-wasting to the average player.

I most likely wouldn't continue using the system as it was presented- not out of angst, but simply because I can't see myself ever putting in the effort to arrange the items needed for such simple gains, and the crafting system has no purpose if you can't reach the level of making good quality items.