Think of Berserk and certain scenes spring to mind, that's the scenery of chapter 348. A gloomy sky with a black Sun, tattered banners fluttering and below everything is a miserable chained dog dragging a coffin to protect a broken lifeless doll from the spear-throwing creatures. This is Miura, this is Berserk, this is why we wait and this is why we will have to wait until the very end.
Every panel of this chapter had a metaphorical meaning to it. The sun was giving the vibes of an eye, flying creatures were representing apostles because the dog (Guts) can't reach them and the peak is the location of the tragedy. Until now all we have seen is the representation of Casca's mind about herself and Guts. We might see the Griffith and Band of Hawk of members in the upcoming chapters. This is post Eclipse Casca, nothing but a broken empty doll.
Schierke and Farnese are now looking for other fragments of Casca's mind. In this journey there is a possibility they will witness eclipse and that might help them understand Guts true feelings, his connection with the Band of Hawk and hate towards Griffith.
It's still a mystry how Casca's mind will be fixed and more importantly does she really want to be brought back? We will find this in the next month.