The Bogleheads wiki helped me decide what to do:
https://www.bogleheads.org/wiki/Prioritizing_investments
Pretty simple. When I started saving, I was already in the top tax brackets so maxing tax deferred (401k) was a priority. Now that I am retired, I can convert the 401k to Roth @ 12%. That's a big tax arbitrage.
I am 100% stable value fund in my 401k to minimize growth so I don't have to pay more tax.
I also did backdoor and mega backdoor Roth while working. That got a good chunk into our Roths that is now tax free. I kept the Roths in 100% stock so the significant earnings are tax free. That's another great tax arbitrage. And could help with minimizing income in retirement if I needed to do that.
Everyone's situation is different. Given a choice, I would want everything in a Roth. Good for heirs, too. But I didn't want to pay 40%+ in taxes to get there.