Joy of Life's premise is silly, it's the kind of scifi YA nonsense you'd write in highschool.
Which is ok, I'm not expecting a masterpiece.
The series however relies on its story way too much, to its own detriment.
Put simply - the show is all about intrigue and plots, with a side of romance and mystery.
Trouble with this - the intrigue is not very clever or engaging, character motivations are shallow or terribly overcomplicated. It's written to work only as long as the plot rushes forward, so you don't notice how flimsy it is.
It also uses the "character decides to do the last mission before retirement, oops" cliche, and it's unfortunately very important to the overall story.
On the technical side, the show looks very nice in a few places. Mostly it's "ok" to watch. There are some fights, especially in the second half, and they're pretty well done.
One aspect where the show really dropped the ball is music. It's weirdly western sounding, like from a 90s/early 2000s sitcom. Quite distracting.
(side note: There's a bunch of talk about chi, levels of mastery etc., but it hardly ever matters. It's a device to lock certain plots into evolving certain ways. This is tied to the characters, which I'll get to now.)
The main reason to watch the show, to me at least, are the characters. They chose very good actors, there are hardly any weak links.
The problem is - the characters are slaves to the story and they come and go only in its service. If you happen to not care about the story, about the secret police stuff, about court intrigue and "The Mystery" of who Fan Xian is, you'll be constantly pissed off by what happens to these characters you like.
I wanna watch Fan Xian and his brother run a book shop, or do poetry battles and flirt with pretty ladies. I don't care who his parents were, or what the two princes are secretly plotting.
Speaking of Fan Xian - he's borderline unlikable. A very special Marty Stu boy who gets away with everything, either because of his super cool fighting skills, photographic memory, or because seemingly everyone in power (with a few exceptions) keeps him protected.
It heavily reminds me of young adult fiction novels, or perhaps Harry Potter.
The romance is interesting at first, because it largely skips the wooing stage, and the whole "will they or won't they", which is refreshing. But then when they are in fact together, it very quickly separates the couple, to introduce two new romantic interests for Fan Xian to flirt with.
The first season ends, of course, with a massive twist, AND a cliffhanger twist. Both are completely pointless and are not really foreshadowed, so you can't be satisfied you called it. (unlike the revelation of who FX's parents were, which was at least decent.)

TL;DR - mediocre to slightly bad show with really good actors and fun characters.