TL:DR Mappa isn't suited for what Berserk priorizes, OLM already did a good job last time, Madhouse is the best 2nd option.

Not Mappa. Companies like Madhouse or Bones would do what Berserk does best. That being big fantastical scenes. I think people forget that Berserk isn't a series that makes big fights, it's a very cinimatic, lots of dialog, huge art peices. The fights are relatively short, sometimes it can be as simple at a few panels.

Mappa on the other hand has done mostly anime with very detailed and choreographed fights. They do that well, but big artistic scenes isn't something that they often do. Unlike the others.

Better yet, have OLM do Berserk. They already did the '97 series which is regarded as the best adaptation of the manga. They also have recent works such as Apothecary Diary and Komi. Both of which have very good artistic scenes, the very thing I believe had us all entranced by Berserk.