Ep4's Voice cast has to be done by the same VAs that were credited in the games credits since they didn't appear to add any new ones there.
From what it sounds like Pretty much all of Ep1-6's voice work has already been done.
I really want Persona stuff to come to NA. I know they'll most likely do it whenever Persona 5 Scramble comes to the West
I don't think BB being Japan only is really a good excuse for cutting Cougar out considering Dengeki Bunko: Fighting Climax came out in the US and had a Border Break themed stage https://www.youtube.com/watch?v=daUUNJ0xHA4