Next expansion

What could or should the next expansion be, fleshing out A4 to the level of the rest of the acts or a Brand new A6 or something else altogether?

A4 was a little rushed to make the Christmas season crunch!

This used to be a big deal for game studios before digital distribution was a thing. Your deadline was basically Summer for distribution to big box stores. Thus LOD basically completed the game about a year later as that content was already mostly designed and planned but just not ready for release initially. They kept patching and adding features even after Blizzard North was shutdown in mid 2000s but it slowed down a lot. That is until recently with D2R so who knows what might be next?

I would not expect it to be very fast after transitions from Condor (D1) -> Blizzard North (D2 & LoD) -> Blizzard (D3) -> Activision Blizzard (D4) -> Blizzard Albany (Vicarious Visions D2R) -> Microsoft (D2R: RotW) -> TBD? ... every M&A adds some amount of confusion into the mix!