My issue: what about the other tasks? With this tool I'd have my task list and my email-task list, in two separate places. Not ideal.
I know it's probably way out of your scope to also build a good general purpose task manager. But I feel like another kanban to manage is one kanban too many.
To be honest that's what I hoped Notion Mail would be. I've landed back to Notion as for task management and something that would autosync my emails so I can "see" them (as in, move them around in a kanban and add notes to) in Notion itself, essentially making them tasks would be the perfect system.
Anyway, I do love the people focus. Makes much more sense than any other label-based attempt.
Best of luck!