Dealing with more complex energy flows than grid <-> home

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Posting this as a general discussion rather than a specific feature request because I'm not really sure how this would best be done, or even if it's feasible. At the moment the config assumes you've got a single energy flow grid <-> home with optional solar and batteries in between. However there are many situations where there's more than one $home that energy can flow to. One example would be a single residence with two dwellings, served by a single grid feed with at least one metered sub-board for the individual units. A variation would be a home business as shown in the amazing PaperCAD diagram below, with the 'M' being metering points:

A more complex variant involving a solar ESS setup has two feeds to the home, one for essential loads backed up by the ESS batteries in case of a power outage and one for non-essential loads that don't need to be powered, for example HVAC:

At the moment Power Flow Card Plus has a single entity $home that all power flows to. The first case can sort-of be handled by treating 'Home' and 'Business' as two entities below the standard $home, but it gets messy when 'Home' has its own entities that depend on it (oven, hot water, HVAC, EV) rather than $home directly.

And it doesn't work at all for the second case, which requires two different $home's, one for grid-only power and one for solar-backed power.

How would cases like this be handled?