There is not much discussion about Leste on the Pinephone site where other OSes are getting more attention.
https://forum.pine64.org/forumdisplay.php?fid=120
https://forum.pine64.org/forumdisplay.php?fid=131
But I would really like to see even a Maemo5 skin for Phosh, I currently have Mobian on my pinephone. Until I can reliably use my Pinephone for navigation, a good audio book player, Bluetooth tethering, and integrate with my Pebble watch I will continue to use my N900.
It is already usable for web browsing, phone calls, and SMS.
I would also like IMs like briar and tox clients, as well as optomised streaming client preferably a plugin based one like Kodi though video hardware acceleration seems to not be implemented yet on mobian.