Further recommendations. Twice as many this time.

(remember, feedback on which songs were good and which ones sucked, possibly by PM, helps tailor recommendations to what you like.)

Setsugetsuka (Yukari) Another Yukari song since you seem to like those.

Lonesome Cat (Miku) Rock song about a cat. Funny.

Tori No Uta (IA) Cover of a song originally by the voice provider. Probably the best example of vocal tuning I've yet come across.

Cloud Rider (IA) Quite energetic, and one of the more prominent IA songs.

Smile Again (Miku, Gumi) I'm pretty sure this song needs to be classified as some sort of mood-altering drug.

And now for the electronic/dance/trance songs. They get more calming as you approach the bottom.

Twilight Star (IA) The first IA song I ever found. Still pretty nice.

Solosail Remix (Miku Dark Append) In a similar vein as Lost Memories and Idiolect. Feel free to let your impressions of those songs direct your interest in this one.

Unlimited Blue (Luka) It's always nice to see a non-Miku trance song. I mean, there are a lot of really good ones with Hatsune Miku, but the percentage is too high.

Starport (Yukari) Very calming and perfect at the end of a long day.

Planetarium (IA) The single most sleep-inducing Vocaloid song I know of. In a good way.

Oh, btw, for Yumemidori, this is the official upload of the creator which won't be taken down.