(don't know how to comment on the task itself, so opening this)

Jonathan,

the property/observableProperties is exactly what we need. Whatever you do to replace it, make it just as simple as it was. There's no need for a zoo of dataRetrievers, if all they retrieve are reflectively accessible properties.

Plus, IMO there's a difference between
a) the data the cell is bound to
c) the visual representation of that data
c) the properties (of the data) the cell needs to observe to keep its own representation synced