Beat this after three years of chipping away at it and I can say it's really good but also flawed. There's a lot of typos and weird grammatical things especially towards the end (the screen you get when beating all puzzles says "pazzle"). I really hate that you can't turn off autocorrect even if you turn off all assists.
The songs are good, though I only ended up listening to two of them most of the time. I haven't gotten the chance (or motivation) to hear them outside of the context of the game, though.
I liked it and I would like to get into more themed Picross/nonogram titles if they had stuff I liked.

After about 150 puzzles, I think I've played enough to where I can give an opinion on this game. There's not a lot to it, it's Picross, it's Vocaloid. I am a very big fan of both of these things, and I enjoy this game decently enough.

I'll start with the positives, obviously the puzzles are fun, and the art is all pretty cute. The special puzzles, where you solve 25 individual boards to fill in a complete image, are probably my favorite part of this game. I thought I would have more to say on this aspect, but it's just Picross, not much else to it, cool game.
I do have just a few small problems with it that I can talk about, though. Probably the worst offender, the music selection is shockingly lackluster, which is never something you'd want to say about a Vocaloid game. They're good tracks, but there's only 18 of them, and only one will ever play during actual puzzle gameplay at a time. There's no way to make some sort of playlist to shuffle through while solving, which can make whatever you choose start to get a bit repetitive very quickly.
The Picross part of Logic Paint S, while I did praise it earlier for being... Picross, does somehow manage to get a few things wrong. The controls are incredibly slippery, which by itself shouldn't be that big of a deal. A minor annoyance, but not something that should ever get in the way... is what I would say, if it weren't for the fact that the game automatically blocks any and all mistakes you might make, counting it as a 'miss.' I get why, there's still stars to obtain throughout each level, but I would much prefer being able to fix my mistakes on my own, maybe after filling in a bit more and realizing where I went wrong that way. This, combined with the slippery controls I brought up, can make for some frustrating misplays that more often than not are completely unintentional.
The game also starts to feel less and less like a Vocaloid game the longer it goes on? I realize that with 345 puzzles to work on, you're bound to run out of notable items eventually, but it really doesn't take long before pictures become just basic items or animals, which may or may not relate in some way to the image you're given for the gallery after completion.

It's a bit of a middling Picross game, with a topic I enjoy very much, but I wouldn't call it bad. Picross is Picross, 6/10. I definitely wasn't expecting this game to have as much as it does.

It has a cute art style, but the interface and sounds need some work. Scrolling over each and every square or button makes a loud tick noise that gets really annoying after a while. The UI is counter-intuitive. You have to go out of the current puzzle and back to the main menu to change the music. The gameplay is just your usual picross, with the finished puzzle (vaguely) resembling an object and unlocking artwork you can look at. Overall, it's fun to play but it definitely needs some quality of life changes.

One day a boy named PinClock was given a visit by a certain Vocaloid. Hatsune Miku was very cool and kawaii, so it was exciting to learn things from her. Not only that, but he'd be rewarded with some cute artwork for doing it. The puzzles were simple at first, but the further they went along, Pin ran into a problem: To be a real star, Miku wanted everything to be Perfect.

So Pin would try and try again. Listening to the same 18 songs about puzzles over and over and over. Did he misclick? Start over. Did he interpret something wrong? Start over. Did his arm nudge an inch as he was moving the mouse to fill in a row? Start over. It wasn't perfect. In Miku's eyes, everything had to be perfect.

He couldn't escape it. The sounds of a wrong input would scare him to sleep, and in his dreams all he'd hear is "you're not perfect". He didn't know what to do. The fatigue from failing to be perfect only caused him to do worse.

By some miracle, the wise Luka Tako in the tub explained to Pin "there's no such thing as perfect." she said, "through your imperfections, you can do anything." And then Pin had an idea.

Anytime he got an imperfection, it only made him stronger. Each start over he had memories of previous mistakes that, although not perfect, managed to pass all of Miku's extreme requirements, just in ways she did not expect. Overwhelmed, Miku bugged out and didn't give me my dang achievement for being Perfect, (they'll fix that the devs have been good) but I know in my heart I overcame the need for Perfection as Miku fizzled away and everyone lived happily ever after.

tl;dr it's an alright puzzler the graying out of parts is weird and sometimes helps too much there isn't enough songs for the game length so while good they get repetitive and the art is a nice reward but do not for the love of god strive to be Perfect it will kill the fun of the game. I prefer the penalty time based systems rather than perfectionism under infinite time.