I find that almost always a projected income statement is the best summary for a business projection. If it is not a good representation of cash flow, you will either want a cash flow statement or something that clearly explains your cash position over time (could be as simple as a line item added after the net at the bottom of the income statement).
I usually have the first worksheet (tab) in an Excel spreadsheet be the income statement, with other worksheets behind that supporting any particular line items that require more analysis/depth. For instance, let's say that you have several products that are in your plans and you have monthly forecasts for each. Many other items in your income statement, such as staffing requirements, depend on those projections. For instance, if you don't launch the 2nd product until later, then you wouldn't hire another staffer until then. I would then have a secondary worksheet with the product forecasts, and possible another with staffing. The summary income statement would reference those pages for sales/revenue and for salaries and other labor costs.
Each time I've done one of these types of projections, the backup pages are different depending on the business. But this format proves to people that I know the business and what will be driving the revenues, profits or losses, and cash balances over time. The investors want to know the overall projections, then they want to be really confident that you understand at a very detailed level what drives the business and keeps it running over time.
Hope that helps. If you want individual help doing this type of projection, feel free to send me a message.