Unfortunately, the option to recharacterize (or "undo") Roth IRA conversions was eliminated by the Tax Cuts and Jobs Act starting in 2018.
Considering the value of your traditional IRAs, backdoor Roths will continue to create taxable income.
but form a positive prospective you may be paying lower taxes now than you would if you put the money into an IRA and let it grow there.
future options to avoid conversion taxes are either to make a direct Roth contribution or to an IRA for which you do not take a tax deduction. it would seem based on the IRA value a ROTH would better serve you.
When you need to start taking RMDs from the IRAs, consider Qualified Charitable Distributions (QCDs) - a direct transfer of money from the IRA to the charity. You do not and can not touch the money. That makes the QCD portion of the distribution non-taxable but you lose out on the charitble deduction. This does have the effect of lowering AGI, which can have some beneficial tax effects. WARNING. Tax laws change like above, so if interested, inquire about the tax laws affecting QCDs in the year distributions will start. QCDs cannot come from ROTHs
