When it comes to economic activities that bear a disproportionate expense on the public, I believe that excise taxes are the most effective way to regulate and contain the negative externalities created by said activities. For example, if you drive a lot, you’re polluting and putting wear and tear on public roads. A gasoline excise is an effective way to directly tax that activity which creates a strain on the public fisc.
In respect to corporate income taxes, they don’t make a lot of sense because a. they are so easily avoided and b. we should really be taxing the people who own the company rather than the vehicle through which they organize their activity. Your not wanting to “let corporations off the hook” suggests an ideological aversion to abolishing corporate income taxes rather than a reason rooted in something more logical and fact based.
In a more perfect society, I think a flat income tax would be good. But in practice, I think a slightly progressive income tax structure would be 1. politically feasible and 2. won’t discourage productive economic activity.
But as a way to smooth out the tax code to become flatter, yes, I would like to get rid of the myriad tax breaks that complicate and distort the clarity and purpose of the tax code. And yes, that includes homeowners’ mortgage interest deduction, 529 contributions, ERISA and IRA contributions, and the corporate tax break on employer provided healthcare.
