Roth vs. traditional
Some investors might assume they need to be dogmatic about which IRA type they choose: Roth or Traditional. But savvy investors often end up with a blend of traditional IRA and Roth accounts, both by happenstance and by design.
For example, someone who could contribute to a traditional IRA in the past may no longer be able to deduct her contribution because of income limits, but she can still fund a Roth IRA.
Moreover, the concept of tax diversification is a valuable one, and argues for building balances in all three account types: taxable, tax-deferred (traditional IRA and 401(k)), and Roth.