I think endfield should have it's own general.
It does not matter to me if the threads are slow.
Every game has a natural lifespan on 4chan, if the arknights thread dies then so be it. The problem does arise if there is not /akg/ thread then someone who wants to discuss the OG, be it the oldfags or newcuties, probably does come to the /efg/ or whatever it is going to be called.
But doesn't that just combine the thread later more naturally if that is the case? So I don't see any downsides of splitting the thread.
Also Arknights gets twice the chances to succeed in divegrass. Haha
That is just my two cents.