Similar to the Photon UI, we are currently running a trial of the Alexandrite UI here: https://alexandrite.slrpnk.net/
Please let me know what you think about it.
Of the three (default, Photon, Alexandria), Photon is my favourite by a long way.
I use dark mode on everything so I have that bias. I find Photon easier to read than the others site to the colors.
The larger image preview is easier to see. I prefer text-only in general, but I notice my eyes are less strained trying to make out thumbnail details with Photon.
The UI layout seems tidier too.
Is the long term plan to keep them optional or phase out some in favour of others?
I think at some point it would warrant a discussion about replacing the official lemmy-ui with one of them, as the lemmy-ui is quite full of bugs and apparently a nearly unmaintainable code-mess. The official devs also started re-writing one from scratch, but I am not very convinced of their approach as it looks again like one of these NIH Rust projects.
Otherwise, currently they are not maintenance intensive to run or need much system resources, so I don’t think I’ll retire them soon. However all of them are quite young projects and there tends to be a certain natural attrition, especially when there are so many alternative front-ends like for Lemmy right now (Voyager would be another one worth trying). So I think some of them will not be updated any more in the not too far future and given the frequent API changes in Lemmy stop working soon after. So don’t get too attached to any of them right now.