1. Will we be getting an overhaul of the calendar, with procedurally generated per-word calendar systems? By this I mean two things - both the mechanics of time passage themself(for example worlds where seasons last several years, perhaps even decades, like ASOIAF, among the more mundane options) and the recording of the passage of time by sapient beings(e.g. a different number of months in a year, the division of time into "eras"(like in the TES universe), an explanation of when year 1 starts(where applicable), etc.)
2. How will spellbooks work? They're a staple of high fantasy and they'll obviously be included, but I see some problems with how to make them both fun and having them make sense. More specifically:
a) How will the generator handle the writing of spellbooks? Obviously this would require mages experimenting during worldgen and then writing their discoveries down, but how specifically are they going to experiment? A human might be able to see potentially interesting venues of further investigation, but how would a computer handle this?
b) Are spellbooks planned to be the one-spell-per-book variety, or the all-encompassing tomes with a bunch of spells contained? The first would be more fun(since it would require more exploration and learning new spells would be more rewarding) but would make far less sense(why, exactly, would a 2 step spell require an entire book about it?) while the second would be the other way around.
c) What would prevent worldgen mages from cluttering the world with 3000 books about the exact same spell?
d) What would prevent worldgen mages from simply discovering every spell there is on older worlds?
e) What would prevent spellbooks going around the world in massive numbers and making everyone a mage over time? If my character can read, what prevents me from simply learning a spell even if I'm not a mage(excluding spells that have prerequests, such as a bloodline or a faith in a god)?
f) Will there be spellbooks less about practical spells and more about interesting experiments that could further one's deeper understanding of the magic system?
Hope that isn't too much.
Well, firstly you're asking about the NEXT arc, not the one whose first release is nearing, so things are still quite a bit up in the air.
b. Single/limited number of uses magic items, such as runes, potions, crystal, etc. are common in fantasy, with some of them usable by anyone, some only by the creature they're given to, and some only by those with sufficient skill/knowledge to use them. What DF will implement remains to be seen, but they probably wouldn't be called spell books.
c. There are numerous reasons for why mages aren't mass producing spell books:
- Trade secrets
- Limited demand
- There are much more interesting and profitable (in whatever currency is of interest to the mage) things to do for a skilled mage than cranking out spell books
- ...
d. There is nothing in particular to prevent everything that's possible to research to have been researched in an old world. There is also nothing saying there won't be cataclysms that causes a new set of rules to come into play, adding to, subtracting from, or replacing some or all of the previous rules. The elimination of a god or containment of a sphere would probably affect any magic that has those as a source, while the birth, resurrection, or growing power of a "god" could introduce new rules.
e. Typically magic requires long and painstaking training and research, so a spell book would only provide meaningful information to people with the appropriate prerequisites (i.e. sufficient study of that branch of magic). Unless you've studied advanced math, the advanced math textbooks are nominally readable to you, but probably not particularly understandable, as they assume you already have acquired the underlying body of knowledge, like e.g. referring to proofs you're assumed to be familiar with, terms with a specific well defined meaning, etc. In addition to this, magic is often described as having verbal and somatic components, so you need to know the words, how they should be uttered, the required state of mind, and the appropriate gestures to successfully cast a spell. A skilled mage might be able to infer a lot from just a spell book together with a known body of knowledge to research/figure out how to cast a spell described, while the same spell book acts more as a reminder than a complete set of instructions to those who know the spell (possibly with the same kind of shorthand and omissions as reminder notes can have). Thus, everyone do not become mages for the same reason everyone isn't cobblers, carpenters, accountants, and engineers simultaneously in the real world: you have to concentrate on one profession, although you can be a dabbler at many, or have some as a hobby. Note, however, that this is just one case. There may be hyper magic worlds where everyone knows at least some simple magic, and there will most likely be other kinds of magic (bestowed by a powerful magic wielding more or less godlike creature/item/force, innate magic in certain races/animals/plants(?), etc.).
f. Magic research is very likely to be available in fortress mode (eventually). Whether research can be jump started or accelerated by acquired arcane research notes (I wouldn't call such works "spell books") remains to be seen, but it's not uncommon in fantasy for powerful creatures blocked from gaining access to our (fantasy) world use minions or other remote control methods to either open gates to let them through or spread information on how to open gates to lure fools into releasing them through the promise of power/riches/knowledge. You can also find examples of notes left behind by defeated enemies or powerful wizards of old being found or located.