All good points. I just like that there is no limitation to the number you can do. Don't have to cycle leves (that even a thing in HW? Or can you force the same leve you want over and over?) You get a bonus for "HQ." I personally have checked the exact numbers on a crafting leve HQ vs a collectable at highest tier. The blue scrip item I always looked for was Dragon Fang earrings. If you keep a healthy stock of dragon fangs (back when I did this, they were 300g or less each and I had plenty. Hardsilver nuggets these days are pretty cheap, since the sand is pretty cheap (at least on my server).

With that combo, honestly, I'd ignore worrying about blue scrips at all on other jobs, unless the "cost to make" a blue-scrip item was sufficiently cheap enough to make it worth the extra exp bonus. I'd estimate that about 7 of the 8 books I bought were all from dragon fang earrings probably earning 0 exp. Fast, easy, cheap.