Thanks to RunningBum, I started to investigate consequences of death of a spouse.
The loss of deductions between married, filing jointly and single status produces a BIG hit on the survivor!
I ran a few scenarios where one of us (me) dies at 71 (not impossible if I don't lose a lot of weight soon). When I made the correction for married/single, significantly more taxes were paid. So much more, I am not sure I got it right. Taxes are money that is not working for you.
Still refining this (looking for bone-head errors), but right now it looks like a good strategy is to move our IRA to Roth totally
after stopping work and before 70.5 (MRDs begin) and 71 (same tax year) when I start taking SS, regardless of the marginal tax rate. Of course, if we both live to 100, we will have paid more total taxes than if we only converted to the top of, say, 15% marginal rate, but
a) it is highly likely that one of us will not survive the other and by that time it is too late
b) total conversion frees us from virtually all income taxes after 71.
Remember, our situation is a lot simpler than most and I am only looking for a strategy by comparing alternatives on the same basis.
I will report back when I am comfortable with the calcs, probably after New Year's some time.
BTW, it looks likely that we will be here another year (which will help a lot), but it is not on paper yet and things are changing daily here.
Cheers from 52°F and sunny Baku.