I've been playing reborn since ep17, and I loved every moment of it. Take as much time as you need to finish this, but I'd be happy playing Episode 19 without the postgame tbh, the game feels large enough as it is. It'd be easier to release the main story as ep19 (letting the puplic test the first half before the full release) and add postgame as a .1 patch (or just call the full package reborn and ditch the episodes alltogether).
Also, can you fix the randomizer so that 7th street shard pokemon don't change? It prevents us from completing the mega ring sidequest since their
