My practical evaluation of the top four:
[] The We
- Requires the most time/effort investment of the top four on our part to start with, and will make the library initially more intimidating. However, the We have an assortment of abilities(instant telepathic communication between members, movement in three dimensions, innate security, ability to grow numbers as needed, no dying of old age) that means they can grow into basically the ultimate librarian, and their straightforward logical nature makes them both trustworthy and highly reliable.
The fact that their home would be the Library, and they would neither be easily capable or at all inclined to move away from it, would also make it extremely unlikely for their interests to diverge significantly away from the Library's.
High trustworthiness and maximized competence as librarians in the long term, but requires a greater initial investment of effort.
[] Cython
- The most politically intricate of the options, in my eyes. Cython is extremely competent, but also cunning, self-serving and callous. However, this option would align its interests much more closely with ours and the Karak's, which makes it much more of an ally than it currently is. Whatever secrets Cython may know - and there are certainly going to be a lot of them - will be a great deal easier to get out of it, and it would be much more inclined to trying to defend K8P if it comes under threat.
Cython would maximize security moreso than any other choice, and is capable of performing the duties of a librarian with extreme competence if so inclined - though I'm not sure if it'd be as invested in that as in security. It's also naturally inclined to seeking out more knowledge, especially exotic knowledge, which will aid in the Library's growth.
The big concern is that it would be much more likely for conflicts of interests to appear between Cython and other people that are also invested in the Library(such as Mathilde and K8P in general), and if that happens, Cython would have a great deal of ability to ensure that things land in its favor. It is very difficult to say "no" to a Hysh Emperor Dragon, and if Cython decides to do things we don't like, we can't really put the dragon back in the box.
Highly competent but least trustworthy choice, but has the most goodies attached to it.
[] Locals
The simplest and most straightforward option, really. The main complications are the conventional ones you have when you aren't an Emperor Dragon or a colony of giant spiders. Competence checks, corruption, bribery, manipulation, infiltration, theft, politics, disagreements, etcetra.
The most interesting thing about this option is the cultural impact it has: The Library would become far more integrated into the identity of the locals, and the locals would be much more inclined to become the sorts of people that highly value libraries.
Simple option, replaces all the unconventional problems with just conventional ones.
[] Cult of Verena
Another relatively simple option. Same "conventional" weaknesses as the Locals, but the Cult of Verena brings the most immediate expertise, and libraries are sort of their Thing, so competence is expected.
The other main concern is that the Cult of Verena is very established and likely has their Own Way Of Doing Things, which could come into conflict with what we want. However, I think this is not likely to be a massive problem, seeing as the religious mandates and cultural values of the sort of Verenans we'd be recruiting are practically identical to our goals for the Library. Honestly, I can totally see us getting along famously with them.
The Cult of Verena would also be an excellent friend to have, and they have some great goodies to offer. We'd be able to much more easily obtain very large amounts of BÖÖK from Verenan libraries this way, we can get that knightly order on board for extra defense(I think Belegar would be quite happy to have another knightly order invested in K8P's protection), and whatever expertise the Verenans have to offer as experienced librarians. Maybe we could even finally get a Divine caster into WEB-MAT...
