Touhou and VN threads were seriously 80-90% of /a/ at all times. Seriously. There was no anime and manga.
And as for the fags whining about Naruto and Bleach threads, have some pasta:
The Bleach and Naruto threads have always been on /a/, and have always gotten the same amount of posts as they do now (well, I suppose there's more now, because of the sages). While the /a/ populus has hated Bleach and Naruto ever since it turned into generic powerlevels, newfags come in to /a/ to talk about it.
Now, contrary to popular belief, the Naruto/Bleachfags that show up on /a/ aren't from Gaia, GameFAQs, Animesuki, or any other shitsux animu forum. Why would they need to come here for Naruto/Bleach threads when there's plenty on their home site? These particular fags are from 4chan. Naruto and Beach are pretty fucking popular, so there's plenty of fags from /b/, /co/, /v/, and other boards that have a "mild interest in anime"(read: read the new narutu chapter every week). Proof: They don't realize they're newfags, cause they've been on some other board on 4chan for a long time. They decide they want to talk about their crappy animu, come to /a/, and look for a thread relevant to their (newfaggy) interests. If they don't find one, they make one.
The difference that the split made in this regard affected only the speed and activity of the board. There'd often be 3 pages worth of active threads, and thus low-powerlevel fags from other boards could have their shit threads and spam F5, whereas high-powerlevel /a/ fags could stick to their threads (that were ignored by the newfags, since they didn't know whatthefuck it was.)
Now that /a/ has become two boards, the number of active threads has decreased, and thus the activity of newfag threads has become much more apparent. My solution? Leave them be, hide the thread, and go make some high-powerlevel thread. They won't understand it, so they'll just ignore it.