This does a clever job of dealing with the multiple varied inputs to a scenario.

A real budgeting scenario might have 2 * 3 * 7 * 4 * 5 * 3 * 9 * 2 * 5 = 226,800 possible outcomes, so the obvious question is what UI do you use to consider/narrow down that beast? You need tools that let you slice and dice that output based on different sets of criteria.

The simplest might be something like, "rule out all solutions that total more than $5000" but you also need things like "I will only pay for a total of 3 streaming services, rule out all scenarios with more than that" and "if I choose not to have a car, then I have to get a transit pass and an e-scooter"

I almost feel like, as clever as this is, the harder problem is the one I describe above.