Everybody complaining (no judgement - I want one too) about no VIII replacing the VII ignore the fact that the V/Va is the one that needs refreshing first, and it could be the 24-70mm f1.8-2.8 that become the VIII.* The VII has a touchscreen, but we all know how limited it is, but the V and Va don't have one at all, nor does it move as much. The V/Va also doesn't have the VII's viewfider, still requiring you to manually extend it when released.
If, and we all know how dodgy that "if" is, we get new RX100s, I doubt there'd be much in the way of internal improvements. Maybe there could be improvements in subject detection/tracking, but I doubt it'd get anything as fancy as the Bionz XR - physical limitations aside (will it fit?), it'd zap the small battery quicker. I'd very highly doubt there'd any change at all to the optics of either the 24-70mm or 24-200mm models.
The improvements I'd hope/expect to see would be a more functional touchscreen like that of the ZV-1 (which on the VI/VII seem more of a software upgrade than hardware), a USB-C port replacing the micro USB, and the auto-extending viewfinder on the 24-70mm model.
The problem I see with expecting anything new, at least in the nearish future, is that there's been zero software improvement with the VII. Assuming the touchscreen isn't single point touch, I don't see why it couldn't be revamped with more functionality than just using to choose your focus point. Menu and gallery navigation, controls, etc. You know, like every other camera has these days (including the ZV-1), and many had before the VII was released. This would only require a firmware update, but it's 6 years later and there hasn't been one.
*Designation is arbitrary. They could make a replacement for each, one being a VIII, the other being an IX; it doesn't matter which gets named what. Or they could get a different name entirely.