Divide Your Roadmap into Top Priority, Optional and Not Focusing On
John Cutler has a really good template for anyone forced into creating quarterly product roadmaps. It breaks down each column into three sections to make it easier to articulate what is/isn't in the plan.
Top priority outcome
This is your main focus for the quarter
These are optional initiatives for the quarter and assume you have the time, support and investment to work on them. It also assumes that your top priority on track (otherwise why would you work on anything else?).
Intentionally not focusing on
This is your anti-roadmap. It's a list of everything you've made a conscious decision not to focus on this quarter.