If you said the profit margin would be higher, then you are right. Why would your profit be higher? If you said because of the fixed expenses, you would be right. Your material cost, labor cost, and variable expenses would have gone up 10% but your fixed expenses would have remained the same. You brought in more revenue because of more sales and you spent 10 % more on material, labor, and variable expense to cover the extra sales, but you didn't spend any more on your fixed expenses. So, less overall expenses, would give you higher profit margin. Make sense? So, let's see how we would make a business plan that would show exactly how your business could give you the salary you want.
There are many reasons for utilizing such a document. Is the final document going to be about implementing a decision already having been reached or is it about analysis and recommendations for a newly proposed activity. As noted above, a finished document may be for internal or external purposes. Externally they are often used to solicit funding for a start_up or joint venture. Whatever the purpose, do not confuse effort with say, a marketing or a production plan.