A business that makes sense and is going to be sustainable in the future is one that has that clear vision within which all the smaller parts contribute to make it successful.
A mobile phone today is slightly bigger than your thumb. Similarly, a business plan is no longer a document of a hundred pages. Nobody wants to know your business. They want to know your views, your goals, your objectives and your plan of action.
If you are someone who shies away from planning, or you don't like writing or preparing documents, nevertheless you are going to have to force yourself on this occasion. I say that because it is such a key document for the future success of your business, such a tool throughout its development to return and refer to.
I teach that you should seek to learn from competitors; obviously never copy another business's idea or what they are doing, but you can absolutely learn from their mistakes or see what they are doing and discover ways to improve it. All of that analysis belongs in your business plan: make sure you have your competitors under the microscope and make sure that is a solid chunk of your plan. That is some of the best research and information you will gather about what will make your business successful in future.