Maybe consider a withdrawal method that exchanges SORR for Sequence of Income risk? That is, change the risk from prematurely running out of money to a method where each year's withdrawal is variable - meaning that there is always the possibility that any given year's withdrawal might be below what you need but at the same time there is a direct relation between the performance of your portfolio and the amount you can withdraw.
Anyway, there are many examples out there
- Something relatively simple such as withdrawing a fixed percentage of your portfolio and letting the long term returns of your portfolio take care of inflation. Mathematically this can never deplete your portfolio, though if your chosen percentage is too high, the size of your portfolio can asymptotically approach $0 over time.
- VPW which has a monotonically increasing withdrawal percentage each year. The actual percentages depend on your Asset Allocation and how many years you expect to be around. This can all be pre-calculated
- "Time Value of Money" which is VPW-like but also takes into account the NPV of any future cash flows like SS, or expected future lump sums, but also uses metrics to guesstimate future stock and bond fund returns, which tends to smooth out the withdrawals over time..
- More complex methods like floor/ceiling, Kitces Ratcheting, Guyton-Klinger and others.
Many, but not all, can be found on this site: https://www.bogleheads.org/wiki/Withdrawal_methods
Others can be found via google.