Future tax-planning is obviously difficult. But I would argue it helps to project a long-term ideal plan, especially around what your withdraw strategy may look like.

For example, even though I have access to after-tax 401k (and in-service distributions), I've nervous about over-contributing to tax-advantage space. Granted there are other factors in play (housing down-payment, short-term savings, health concerns, future tax rates, marriage, children) and everyone has their own set of circumstances to navigate.

I really do idea of ~5 years of expenses to ramp-up to a Roth ladder, as that (for now) seems like something that would work in my own set of circumstances.