I read manga sort of frequently, but it's always a pain trying to find new series. Particularly, manga that aren't at the top ranking because they're already finished scanlating. Most finished series that are completely translated tend to drop in ranking...obviously because they're a finished series. The top ranking manga tend to be series which have active scanlator groups working on the series and people are keeping track of the series.
I definitely think that I missed a lot of these types of series because I don't usually actively look for these them. I'd like some recommendations for these types of series. Thanks

I'd recommend Annarasumanara! The art is absolutely gorgeous and if you like mystery, you should definitely check it out. 🙂

» We are such stuff as dreams are made on, and our little life is rounded with a sleep. «

Here's some underrated stuff from my completed list. Some of these were barely even discussed while scans were being released, which is a shame.

Buzzy Noise
Fukanzen na Hito no Tame ni
Helen ESP
Kasane (MATSUURA Daruma) (the popularity of this one is debatable, but I never see anyone talking about it so I put it here anyways)
Kuroha to Nijisuke and its sequel Kuroha to Nijisuke: Kuroki Majo no Divertimento

What genres do you like? I tend to like shorter, more slice-of-life stuff so here are some of my recommendations.

Akuyaku Reijo nano de Last Boss wo Kattemimashita
Aria
Bonnouji
Chichi to Hige Gorira to Watashi
Emperor to Issho
Seirei no Moribito
Tsurutsuru to Zarazara no Aida
Working Holiday

♪( ´▽｀)

Yumekui Merry
Sengoku Youko and Hoshi no Samidare
If you like more action based stuff.

For romance stuff you can try
Taiyou no Ie
Kamisama ga Uso o Tsuku.
Utakata Dialog
Machida-kun no Sekai

Seconding Bonnouji and Between Smooth and Rough

in need of romance?
uncommon, sad, sweet

I'd highly recommend Yugami-kun ni wa Tomodachi ga Inai if you haven't read that - it's a longer slice of life series

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It does depend to some extent on what sort of genres you like. Personally I have a number of series I like that don't seem to ever have been popular, but they're still great in my book. From my current collection, Ginen Shounen, Aishiteruze Baby, Bitter Virgin (warning, may be a little hard on some readers as it deals with rape trauma), Shion no Ou, The World God Only Knows, and Uwagaki are all finished, and all pretty good. There's also ones like Erased which is officially available for purchase, along with many others. If you want the licensed items it'll take a while longer.

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Yumi to kurumi
Natsuyasumi no Tomo

buUUUUUUUUUUUUMP!

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Seconding Yugami-kun ni wa Tomodachi ga Inai

Also

Barakamon
Koe no Katachi
Liar Game
Majin Tantei Nougami Neuro
Watashitachi no Shiawase na Jikan

Seconding Kasane by Matsuura Daruma. The art is quite misleading as if it's a yuri but the actual story is not. It's tragic, deeper more than that.

The rest :
Muchuu sa, Kimi ni — not much discussion going on and it's a oneshot story you can digest in one sitting.
Tsukikage Baby — from the popular Kids on the Slope's author. It has powerful narration. You can't miss it.
Piano no Mori — just completed few years ago. It's old but still remarkable.
My Broken Mariko — from notable new and talented author. It shows great emotion and characterization. Recommend.
Boku to Kimi no Taisetsu no Hanaahi — the reason why I put this here, because it's between underrated and popular. It got licensed and people forgot about this sooner. I recommend you to buy the digital. It's worth it.

Hate to admit, I have a short memory so I can't remember many titles I have read. And I'm not sure if it meets your liking either. If you are not satisfied, you can make full use of "categories" section/advanced search and go from there on your own.

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I'm seconding Hoshi no Samidare. I still don't understand how it never got an anime adaptation. It was a very good action manga and should be more popular.

Here are some fully scanlated manga that I think are good, but don't get talked about often (OP didn't specify any genres, so...):

• Smells Like Green Spirit
• Udon no Hito
• Watashi no Shounen (TAKANO Hitomi) (OK this isn't that hidden, but it certainly got overlooked because of its subject.)
• Saraiya Goyou (This isn't that "hidden" either with the anime adaptation and whatnot, but hey, some people consider it "old" and don't give it a chance)

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