I don't see the retcon as something so bad and not nearly TRC, really; Noah can be at the same time a collecting machine and a capable magician *shrugs* but that's me and my very personal opinion.

With the knowledge I understood it as having universal excessive knowledge can bring you to madness, hence, it's bad. Not as knowledge is bad per se.

Soul Eater Not. Maybe I have my yuri goggles constantly on these days, also I can't read Japanese to save my life, but omg, this manga.