What is Rom ? Is he good or evil ? Does he hide the real yharnam on purpose or is he made that way ?
Really interesting what happens after you kill it.
Rom is nothing, vacuous. Rom gained so much insight that he was elevated to what you see, but he's unable to share any of his knowledge because his brain is fried. I think it's reasonable to think that Rom's friends might have started Mensis considering the talk about their brains being "aborted" when they tried to contact Mergo.
One thing that I don't know: What did they do at Byrgenwerth? We know Laurence and his Healing Church peeps used Great One blood to try to become more like them, but how did Willem get to be so old and and get that weird shit growing out of him?
Also, if Rom was a person who was "granted eyes", and he was keeping the barrier between the Nightmare and "reality" in check, did Willem want us to kill him or not? Basically, what the hell is the deal with Willem, Rom, the Amygdala monsters, Patches and the Lecture building that's somehow floating around in the Nightmare? These are big questions, I know, but probably the ones that are giving me the most headaches.
I think Willem is kept alive by Rom somehow. That's why he wants you to kill it, and why you see notes saying that Rom keeps Master Willem from his students. I also don't actually believe that Rom was ever doing anything that important, as far as I know nothing suggests he was doing something like that, simply that Rom knows a lot. He hides all manner of rituals, but he only hides them because he can't express them. I also don't think the Healing Church was originally trying to become Great Ones, but rather just communicate with them. That's why they used the Old Blood, which isn't necessarily Great One Blood (and seems to be the opposite based on its effects).
But anyway, the way I think of it:
Willem just wants to know about everything, that's why he likes eyes and knowledge, not pretension or blood.
The Healing Church and Laurence try to use the balancing effects of Beasthood to further the understanding of the Great Ones, and eventually modify blood ministration further seemingly to turn humans into great ones themselves.
Mensis tries to become great ones through arcane knowledge alone, not beasthood. I think they might be the "pretension" aspect pushed further. The One Reborn and all that shit with the baggers don't make no sense.