Can we simplify tax structures without it being called tax increases?

Some of the proposals for changing the way personal income tax is figured in the US are suggesting exactly what you suggest. They recommend, for example, getting rid of a lot of the deductions such as the mortgage interest deduction and the deduction for charitable giving, and then lowering the overall tax rates. So, again for example, you can't deduct your mortgage interest or charitable giving, thus increasing your taxable income. But, your tax rate on that income is lowered from say 20% to 13%.