When we decide to begin using our savings, how should we do that? Income from bonds?
The taxes, if we sell, will be a killer. Suppose we use the IRA and 410K equity funds to build a 'laddered' bond portfolio
and draw from that? Does that make sense? Is it do-able?
It's nice enough to have $400K or so built up, but preserving the value while trying to get to a position of using the
money seems to be a real ponderable.

Once you determin how much you want in bonds it does make sence to have the bonds in the IRA since everythig you take out is subject to regular tax. Have stocks outside as the gain will only be taxed at 20% max when you sell.

You say taxes will be a killer when you sell. They (capital gains)are less than your regular income tax on your salary.