I agree with your idea.
Assuming you want to have one separate dictionary of parameters for each model? If so, each of those dictionaries can reference the same "Global Bus Data" dictionary, as you said.
If your top model's parameters are needed by the lower models as well, you can also create a hierarchy of parameter dictionaries that way. The data dictionary of a model would reference the dictionary of the parent, and so on. If you do this, then you technically only have to reference the bus data in the top model's dictionary... since it would need to be used by all other child models anyway.
- Sebastian
