OK, after some overnight reflection, here are my final thoughts on "Litchi Island" (see below):
I loved it, and I've decided that yes, I would personally call it a masterpiece. It's an artsy, gentle slice-of-life BL with a simple but compelling story, exceptionally good acting, lovely cinematography and rustic island beauty. It requires some concentration to watch (and as mentioned yesterday, a big screen set to UHD), not only because of the tiny English hard subtitles and small screen text but also because the dialogue sometimes moves along very quickly, plus the editing is a bit choppy. The translation, while generally good, is stiff and not without some outright errors. I assume this is a low-budget indie production, but it doesn't feel low budget.
Yes, it's a real Chinese BL, not a bromance. It also has a dig at Chinese censorship. It amazes me that this got through the censors. I will definitely re-watch this if it doesn't get pulled by the censors in the meantime. (That's a clarion call to watch this before it disappears!)
The closing credits are long, thus the total runtime is actually quite a bit less than two hours - so it's not a big time investment, especially by Chinese drama standards.
The playlist titles are all in Chinese, but you can just look at the descriptions to determine the episode numbering.
Does it have a HE? Yes - but not without some pain and inner struggles along the way.

p43425:
Now watching episode 1 of "Secrets Happened on the Litchi Island", a little known but highly rated Chinese BL which just recently finished airing. It's only seven episodes with a total runtime of less than two hours, and so far it looks quite good. Warning: Hard subtitles which are fairly small, so unless your Chinese is really good, it's essential to watch this on a big screen.
Youtube playlist: https://www.youtube.com/watch?v=lMa1K9n7aPQ&list=PL-CWu74qAe0yVW9kUOx_UDuBzYdQl4fZ3
(The seven episodes are all there, plus five hidden files which might be yet-to-be-released extra content.)

p43425:
In addition to watching this on a big screen, I strongly suggest setting resolution to UHD - not only for the beautiful cinematography and island scenary but also so that the tiny hard subtitles and small screen text are more easily legible.