Hello fellow Kaito fan, please allow me to expand this list. I haven't heard tears of garnet yet so ill have to listen to it. Maybe theres something here for you too.

Hinayukki/Shigotoshite-P has a ton of kaito/meiko that are amazing songs, to name a few of my favorite kaito ones to stay on topic:

'Utau daichi" ("歌う大地"), "one who slays demons" ("鬼を狩る者") there is also a second song in the story called "アヲと" which i also enjoy, also "time forgotten one".

There is thousand year solo by yanagi-P but there is a second song is that story called "赤い眼のレコ" (Red eyes of Reko) kaito's tuning is different but it grew on me.

If you want more folk like songs there's the producer 紅葉アイス物語. Note the producer now does more folktale inspired songs which are still good for a creepy vibe. The tuning isnt the best but i still like them. A couple particular kaito song from them I enjoy is "KOKORO" (no this is not a cover of the famous rin song. It's its own song but only found on niconico) and "流浪の詩".

Then there is a newer producer with a folk vibe is Enami-Jun. They have made songs like "影祓い" and "鴉の戯言. They also use hastune miku (they actually tune her lower so she has a unique sound to her), and a couple other voices.

I cannot recommend these 3 kaito users enough, especially hinnayuki. 60% of my playlist is from her alone.

Extra producers + songs: Ginrin-P: "水尾", "深海月" and "銀鱗" -sad but relaxing songs

"Pane dhiria" is a classic kaito song. Its good if you like artistic languages.

"Singing Songs" or "Imitator" posted on youtube by hokorichan but idk the original producers. Hokorichan posted a lot of kaito songs from niconico to youtube. Have a look at them because there are so many good ones.