I'd be perfectly fine with From Software continuing to make Souls games every 2 years or so, and keeping it as medieval fantasy. At the same time, this will give them the funding ability to create new properties like Bloodborne.
Of course, we want to see some new stuff. They have to be very careful with new IPs moving forward. Will they break the mold entirely with the next game? It's hard to say. It will be fun to see what they come up with.
Either way, I'm down for a Souls 4, and a Bloodborne 2 while waiting for another new IP/revisited old IP.