sweet fuse at your side
my absolute fav.

How about Steins;Gate?

I'd say OMGWTFOTL but that's kinda high on drama.

NO

eden*

Say no more
G-senjou no Maou

Some suggestions thrown here although I haven't played them (I've seen the anime or simply they caught my sight for now):
Fate Stay Night
Steins Gate
Cho Dengeki Striker - http://store.steampowered.com/app/321190 (never heard about this one but I found it some weeks ago and seems to have some promise)
Danganroppa I've heard it's very good too
On that side you also have the Phoenix Wright Ace Attorney

For now these are what I remember :)

50 shades of bird.

Leviathan - The Last Day of The Decade is pretty coolio.

I must say that im not into it about VN, but i'm actually waiting for Dangaronpa on Steam and i will get Aviary Attorney eventually :3 ~ Cinders looks pretty cool 2

I love the visual novels about solving crimes or something like that , other than that ... meh D:

U can also get the Sakura games wink wink

Persona 3/4.

;3

Why does it have to have a happy ending? lol

Edit: /s

I'm not sure if you're looking for otome or the likes, but Voltage games have some good story and happy endings on mobile. There have been many recent good Vita releases as well. I really liked Sweet Fuse on the PSP/Vita. It reminded me a bit of Danganronpa. I'm not sure how much you played from Amnesia: Memories, but that game had some really good routes, especially the unlockable (Joker) one.

I was going to recommend Fate/Stay Night but then I read "without much tragedy". Afraid I can't help you in that case.

Katawa Shoujo
If My Heart Had Wings
The Fruit of Grisaia
Narcissu
Asphyxia
Clannad
You can check out more here: https://vndb.org/

 >good story
 >happy ending

Anything knows something that fits? :S

View attached image.

Every Goes to the Rapture.

kek

Sekien no Inganock, Shikokku no Sharnoth, Utawarerumono, CannonBall, Tsukihime, Kagetsu Tohya, Fate/Stay Night, Fate/Hollow Ataraxia

Ever 17 is pretty widely regarded as one of the best VNs ever, if you somehow haven't played that.

And if you have access to a DS, 9 Hours, 9 Persons, 9 Doors is one of my ten favorite games of all time, in any genre.

I was recommended planetarian but honestly I don't know enough about it. Looks like you don't have it in your wishlist, but I'd have thought you'd heard about it, so is it sad? (The summary text says it's heartwarming, so I'm not expecting it to be another "nice boat," but...)

Cinders.

Analogue: A Hate Story
It's not like a "normal" visual novel, but i thought the history very interesting.