Hal Varian has a short article on tax reform in his NYTimes column. I agree with him that one of the most desirable but also achievable reforms would be to expand and simplify "the current messy system of tax-deferred savings, including I.R.A.’s,
401(k)’s, 403’s and Keough plans. We do not really need all those
different plans and having one, simple tax-deferred savings plan would
make a lot of sense."
The graphic below shows how under the current system the marginal tax rate rises and falls arbitrarily.