Another consideration. Should the business plan be a document that is focused on selling an idea for a product or service? For many years I worked in a company that did not want anything in a business plan that could be construed as showing a bias towards or against a project. The mantra was to only present facts in the business plan. The Operations Research Department was there to review the analysis as being unbiased. To handle the "what if" scenarios or sensitivity analysis we prepared a supplemental analysis documents which were mostly financial oriented. Personally, I like a factual approach and use the presentation of the final document to point out the conservative aspects of the content.
Next you will need to carefully examine what actually goes into your offering. How many hours does it take to create those one_of_a_kind bracelets? How much does it cost to bake a dozen of your special recipe cookies? How much research goes into "whipping up" a website? Making tangible goods requires space. Do you have room to grow enough squash to actually generate profits? Are these numbers you could sustain beyond the occasional personal or family use of your product or service? The business planning process can be very helpful to "accidental entrepreneurs" as it allows you to decide which ideas are best left as hobbies and which ones could provide some real cash flow.