That is a great thing to make sure you have in your business plan, that your business will be built around those real customer wants. Do not make callous assumptions, or statements like "I know what people want", "People are going to love this", and so on. Have you done your research? Do you really know that the people you will be targeting want your product / service, and crucially do they want it AT THE PRICE that you will be offering it at? Whilst confidence in your plan is fantastic, you must make sure that it does not lead you down a blind alley along a path that is not desired by your target market. Don't assume what customers want, do your research and make sure that is clear from the start in your business plan.
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.