Need better control of updates on insert, delete, setvalue/UI control change here.
Sometimes one might use an insert or setvalue to move data from a raw data location to a SOAP envelope. No need for rebuild or recalculate there.
Sometimes one might make a setting with setvalue or with a UI control that one knows is the trigger for a "dynamic dependency" in the model. Would be nice to be able to easily say that the setvalue or the UI binding's setvalue should trigger a rebuild.
Put another way, it might be nice to have a UI binding that is capable of moving a whole subtree to the instance. We have that right now with copy in select/select1, but we need other controls like custom controls and tree widgets that can do the same thing.