+1 to explore slicing for program and portfolio...
Def some clues in Jeff Patton's PDF: https://www.jpattonassociates.com/wp-content/uploads/2015/01/how_you_slice_it.pdf
Maybe a little fodder in SA too: https://www.scaledagileframework.com/right-sizing-features-for-safe-program-increments/
> In a subsequent article I’d also like to explore slicing of value at the portfolio level, and getting the entire system to think in terms of slicing by value e.g. a project or an initiative that only spans 2–3 months and the portfolio itself has a WIP limit on it.