What about bonds? How should I model my portfolio's bond allocation?

Within Plan Settings > Bonds, you can define a portfolio-level bond allocation. You can click-and-drag the plot or open the Advanced editor UI to define exactly how you’d like that allocation to vary over time.

Any accounts in your plan that are set to use the plan growth/dividend rates will then behave as if they contain the mix of stocks/bonds you’ve defined.

In the future, if you’d like to see options added to ProjectionLab to define more granular asset allocations across a wider variety of asset classes, here’s an item on the public roadmap you might like to upvote and comment on.