Any advantages or disadvantages?

I (55m) am a retired police officer with a 457b and earning a pension. My spouse (56f) is a teacher and has 4 yrs until retirement and her pension. She is currently contributing to a traditional 403b. We are happy with the amounts in our 457b and her 403b. Our pension incomes will more than cover our basic living expenses in retirement with some leftover. We are considering opening a Roth 403b for her last four years before retirement.

We are currently in the 22% bracket but should be in the 12% bracket when she retires. We plan on Roth conversions during the gap years until we decide to take our social security. We do not have a brokerage account to pull from instead of my 457b. I just opened up Roth IRA's for us last year so the 5 years will be up when we turn 60. There is very little in each Roth IRA (<$5,000).

Questions:

1. Does starting a new Roth 403b in the 22% bracket make sense since we will be in the 12% bracket in four years?

2. Is there any advantage to maxing out her contributions to the new Roth 403b up to $32500 and me pulling out the equal amount out of my 457b (at 22%) to maintain the same lifestyle? Example: Not having to wait 5 years for Roth conversions.

3. Or are we just adding my 457b withdrawals to our earned income for the year and should wait for our gap years for standard Roth conversions?

For what it's worth Boldin Retirement wants us to start Roth conversions this year and fill the 22% bracket for the next several years. I am considering filling our 12% bracket in four years from ages 60-70 instead of Boldin's recommendations. If our 457/403 continues to grow untouched for 21 years then RMD's will put us borderline IRMAA charges and borderline 24% bracket.

We are both healthy with longevity in our families.

Is this one of those instances I need to speak with a financial advisor to crunch all the numbers?

Thanks for any help.