First off know when to touch base. In your business plan make time for scheduling meetings. Many people overlook this. You need to show how you plan to monitor growth and when you plan to do this. Being proactive, such as scheduling weekly meetings, will help add needed depth to your business plan.
Don't focus on predicting actual financial figures. Life doesn't work this way and business plans shouldn't either. Focus on budgets. What are your goals and expectations? If you show a possible backer that you understand financials and leave room for movement then you are proving responsibility right away.
The devil is in the details! When you rework a business plan the key is to provide lots and lots of data. Don't write "monthly management meeting" when you can say "30 day marketing growth review." Let people know exactly what you are talking about, what the goals are, and what your plan is. Too many times I run into people who are afraid to put details in their business plans out of fear the concept will be ripped off. While you have to be careful, you will not find any backer ready to invest money without the details.