I just saw your last post and realized now that you’re asking a different question. I still use the Retirement and Cash Flow Forecast templates in retirement as the ability to model scenarios is quite good.
One thing I did before retirement was to group various asset/investment accounts into categories based on how I want to spend out of those accounts, track returns, and withdrawals/spending from each asset or investment category. I use a mix of the Net Worth, Tags Report, etc. and my own legacy sheets to do the analysis and tracking. I use a risk-based guardrails approach for decisions on significant discretionary spending that factors in the historical (returns) and the projected (cash flow). I keep a rolling projection that goes out until 2055. This is basically focused on ensuring I have clarity on:
- Investment returns across various categories with the ability for me to model what, if any, changes I expect with future returns
- Recent and projected expenses with a clear separation for normal monthly spending (non-discretionary, typical monthly discretionary like dining out, clothing, etc), and significant discretionary spending (daughter’s wedding, vacations, estate gifts to kids, new car, charity, etc).
The approach I take for significant discretionary spending, is to set up basically a budget that is then modeled in Tiller accounts as a liability. In the Cash Flow template, these are modeled as cash outflows. I did that before retirement as I like keeping my monthly and annual budget vs. actual analysis “clean” by keeping major discretionary expenditures separate.
I’m not sure any of that addresses your question, but it’s an approach that has worked well for us. I initially expected I’d stop using the Retirement and Cash Flow templates, but found that these both have been helpful tools during retirement for me.
My original reply before I saw your clarification about your question 
I have found the add-in Retirement Planner template for Tiller to be an excellent additional tool. This leverages the Cash Flow Forecast template and provides a great deal of flexibility in factoring in small or significant changes (expenses, income, returns, etc) these can be defined for a specific time frame or as one of changes.
I use other online tools for retirement analysis and also output from the CFP models to compare to the results I get using the Tiller combination of the Retirement and Cash Flow templates. I’m quite impressed with the accuracy of the modeling. Having this in Tiller gives me greater flexibility to do more detailed scenario analysis.