@ansettax
2020 is a done deal. If you did a rollover tomorrow, it would count for 2021 not 2020. You’re going to have to take the hit on your 2020 tax return and then think about how you want to handle the situation for 2021.
What you have now is a Roth IRA, and a traditional IRA that is partly pre-tax and partly after tax. You can leave it as is indefinitely, end it will just mean that a small proportion of your IRA withdrawal‘s in retirement will be tax free because they come from the after-tax basis in the account. However, you probably don’t want to do another back door Roth conversion without making sure you really know the rules. If you want to contribute after-tax money to an account in your name (because it is your only option given your spouse’s 401(k) and your income situation) then you can either make a nondeductible IRA contribution to your traditional IRA which will increase your after-tax basis in the account, or you could do a back door Roth but you would have to convert your entire current IRA balance. This could result in a substantial tax hit now, but you would never pay tax on it again. Then in future years, your back door Roth conversion would be a very simple matter, because you would open a new traditional IRA, make a nondeductible contribution, and then fully convert it.
You may want to talk to a professional financial planner. I am also in a position where I am trying to figure out whether to convert pretax money to Roth money. One of the factors to think about is that in retirement, withdrawing from a traditional IRA or 401(k) also makes your Social Security taxable. If all of your money was in a Roth account, then your Roth IRA withdrawals would never be taxable and your Social Security would never be taxable either. The problem is paying the tax to do the conversion, and whether paying the tax now pays off in the long run, which is too complicated for me to come up with a good answer at the moment.
Finally, I don’t understand your comment about moving money into a 401(k), or maybe I misunderstood you. Your retirement accounts are completely separate from your spouse‘s retirement accounts, and you can’t mingle the funds. If you currently have a traditional IRA and a Roth IRA, those are your accounts regardless of how you funded them, and you can’t mix the accounts with your spouses accounts. The only way you could put money into a 401(k) is if you went back to work.
