@OP, I think you're right in the sweet spot, or close to it. I'd continue to monitor your after-tax and Roth contribution amounts to make sure you have about 5 years there, then keep plowing anything extra into pre-tax to continue to get the deductions.
One thing to remember is that only the contribution portion of your Roth can be counted towards your pipeline funds, not any earnings. You probably have some earnings in that 13% Roth that you'll have to not count towards your 5 year pipeline (although those funds can count towards your FIRE stash for purposes of the 4% rule).
Finally, because of the exact rules for the Roth pipeline, you can actually make do with a little over 4 years in your pipeline most of the time depending on the exact timing of your conversions and withdrawals. For example, you can have four years of spending in your pipeline, convert 1 year of expenses on December 31, 2017, and then withdraw that 1 year of expenses on January 1, 2022 and fulfill the IRS requirements for the 5 year rule. I wouldn't recommend cutting it quite that close for several reasons, but technically you can.