And while I guess one could be more selective of your employer, your ability to put that much away relies on something largely out of your control (providing one and any matching).

Our goal for the last three years has been to max out a Roth IRA for both me and my wife (spousal IRA). It's within our control and $11,000 is a more reasonable amount for us to stretch to save than a really difficult $18k. And assuming we play our cards right and compounding interest does its magic (5% to 7%) minus inflation, that should be enough for us. $400k in principal + interest = $1million (4%) to $2.8 million (8%).