On highlight canvas you can auto group by 'tag' but not by 'tag group'. It would be useful to group by 'tag group' because I have already done the work when tagging to group these highlights into sensible groups. In this screenshot for example, all the green highlights are positive comments and I'll likely want to put all of these into a single insight. All the pink/red highlights are usability issues I need to sort through; it would save me time to be able to quickly sort these into their respective groups.