This is just a suggestion for a work around which can be implemented now, but have you tried doing this with Custom Lists? Very suitable for brief notes, easy to share via a link, can be public or private (and that can be changed) and you can organise them however you want. I personally find them easier to scan through than my full Completed list and now mostly use the Notes section to remind myself why a title has gone into the black hole of good intentions, erm my PTW list.
I have it in my head that custom lists set to private are viewable via link if you give the link to someone but I've not done that so it would be worth checking.
It's not an exact overlap with what you want of course, but it might be ok enough for now.
