“instead of asking people to rank things on a scale what you do is you give them some list of attributes categories and you say out of this list what's the most important to you and what's the least important to you and then you calculate tally all of that up”

Use MaxDiff instead of 1-5 ranking to actually prioritize features

Likert-scale feature rankings bunch every option at 'kinda important' and tell you nothing. Use MaxDiff instead: force respondents to pick the MOST important and LEAST important from a list, then score each item as most-count minus least-count. One founder ran this and found his planned roadmap scored near zero while a harder, unsexy feature scored highest.