My preference for the zfold devices will be a bigger outer screen. Not as big as the Flagship killer like S22 Ultra. But atleast the size of Zflip i.e 6.7. So the overal dimensions of the device can increase. So there will be enough space to integrate the S-pen inside the phone itself and can introduce long lasting batteries as well. I hope samsung will come up with some solutions for this for the Zfold5.
Well hopefully a wider screen will come eventually. My Z Fold 4 is much more usable for me over the Z Fold 3. But a bit wider still would be great. I'm not really sure practically how an S Pen would be made to fit. Takes up a lot of room inside the phone. Along with the room the hinge needs, you'd probably have to take a hit on the size on the battery. It's really cramped inside the folding phones