Conceptualizing Model

I am conceptualizing a model for the WA apple industry. A sample of growers and packers would be surveyed for data. The project would estimate the full econoimc impact of the apple industry on the state economy and cover fresh apple production, fresh apple packing, apple processing (into juice, etc.) and ensuring that international exporting is also fully evaluated. Only the apple industry (no other fruits) will be analyzed, so it excludes pears and cherries that are also major for production, packing, processing and exporting for the state and are already embedded in the state model. From a previous post and reply, I know that fruit farming sector includes fresh apple packing. My questions are: 1) Is it appropritate to built a new sector - apple farming - with the activity option using industry spending pattern data collected in the survey we would conduct and include it in the state model? This would be truly only apple production (We will also build a new separate sector - apple packing - with industry spending pattern data also collected by survey.) 2) Can I do 1 above and leave the existing fruit farming sector "as is" because I only want to consider the incremental gain we would estimate for the apple sector? 3) Regarding apple processing, I can also build a new sector with survey data I get for the industry spending pattern. Again, I would leave sector 53 and 54 "as is" since this is incremental change. 4) By interview we would also address the international trade aspect of apple exports to other countries from such activity as apple shipping from major state ports, specialized apple export agents/brokers, etc. We would create a new sector with estimates of the amount of direct output (net of output at the wholesale level), direct export jobs, direct export-related employment compensation,exporter's net proprietor income, OPTI and IBT. Again, we would leaving any existing export activity in the state model because we will only measure incremental change. Is this a reasonable approach or do you have other suggestions tha tmight simplify the analysis? Thank you.