Discretionary spending budgeting strategies

I'm in my mid-30s and building toward early retirement. My financial plan uses conservative assumptions (3% real returns) to ensure we never run out of money, but I suspect actual returns will be higher over the long run.

Should discretionary spending (like travel) remain fixed based on conservative projections, or should it flex with actual portfolio performance?

I'm experimenting with an age-based travel budget that uses a 5-year rolling average of real returns:

• Base floor (if returns hit my 3% baseline)
• Age-based ceilings that scale up over time
• Linear scaling between floor and ceiling based on actual 5-year performance
• If returns drop below baseline, floor reduces proportionally

The idea is that while conservative planning ensures security, if markets deliver historical averages, the performance-based approach lets us enjoy that upside without compromising the baseline plan. The age-based component should theoretically recognize that travel preferences/needs change over time.

Has anyone implemented something similar? Am I missing obvious pitfalls? I'm curious how others think about this trade-off between conservative planning and present enjoyment.