was watching last valerian trailer and it hit me that i can't quite remember anything like that in manga, hundreds of alien species, new worlds exploration, giant space hubs, mass effectish style

You can read the OG European comic from 1967 onward or watch the 2007 anime adaptation but such Japanese offerings are nothing rare too.

Space Dandy, MATSUMOTO Leiji´s exhaustive body of work, JRPGs as Star Ocean, the new line of Star Wars manga,... Space opera settings with aliens are as trope-y as the genre gets.

I also read EU/US comics and am a librarian.
Manga-Masters, My ANN-Lists + Imdb

Uchuu Kaizoku Captain Harlock and its related series would fit, I think.

Five Star Monogatari, too.

It's really hard to find newer space themed mangas.

You'll find plenty of them if you look at mangas published in the 70's and 80's, however... Even the original Valerian was published near the beginning of that time.

Here's some that I've read/want to read (ignoring those already specifically suggested):
Terra e...
Sennen Joou
Ginga Eiyuu Densetsu (FUJISAKI Ryu)
2001 Ya Monogatari
Cobra
Hoshi no Koe
Hoshi o Tsugu Mono
Kodoku Experiment
Ginga Tetsudou 999
Hi no Tori
Kyojintachi no Densetsu

HOSHINO Yukinobu seems to have a lot of more modern space themed works

[img]http://i.imgur.com/9BHy24f.png[/img]

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