Pennsylvania Raising Income Taxes?

PA has a rather regressive income tax scheme (it's flat, but the deductions that can become available tilt to the more well off). So I would like for them to implement a progressive part of the code with any tax increase: right at the top everyone subtracts say $15k from their total income. This will greatly reduce the total taxes paid by those at the bottom of the income bracket, while still leading to higher overall revenues if combined with an appropriate percentage increase, maybe up to 4% instead of 3.57%.