My team uses Asana a bit differently to fit our needs.
There is filtered view in a project board that I use daily that I would benefit from having quick access to. The separation of Work, Plan, Workflow, and Company on the side already hinders my ability to see everything I need at a glance, but at least adding my favorite views to my sidebar would be helpful.
Or is this regardless to the new sidebar redesign, and you are simply asking for the ability to star saved view tabs? (of projects, portfolios, workload, capacity plans and other views of surfaces?)