So here's the problem with the tome and codex recipes for the rarity prov house, as I see it.
You can't, EVER generate enough manuscripts to need to use the RPH to make those two types of book at the increased cost over the regular bookbinder. It's just not worth the extra cost vs doing the work in your bookbinder.
Since the main source for fast easy (relatively) manuscripts IS the RPH, the process of making a tome or codex in that building is a double hit. First, you get the whammy because you've stopped making manuscripts to do something else. THEN you get the increased cost whammy of making the book in the RPH instead of the bookbinder.
Both recipes should be completely reworked if they are to be anything more than a pair of spot fillers in the RPH menu. It just makes far too much sense to throw some glue on the bookbinder and do all of the 2nd and 3rd tier work in that building as things are currently costed out.
*IF* those recipes were actually cheaper than the bookbinder cost, then I'd have some nail-biting to do over my production choices.
Manuscripts or tomes? Manuscripts or codexes? What to do? As it exists, manuscripts is the only viable choice.