There’s a lot of un-used space on the left and right side of the list, space that could be useful for a lot of other things.
Typically on the left there would be a navigation sidebar, so instead of having Lists, Due and Tags at the top they could be on the left side. Either on separate tabs or in collapsible sections. I realise that alludes to mouse navigation but there’s no reason to avoid mousing around even if you have incredible keyboard shortcuts.
And on the right would be additional information about the selected item. I suggest moving all the Notes/comments from below the item to a right-hand sidebar so it looks more like the chat it is than a sub-item.
Thanks for your consideration.