Ginga Tetsudou 999

Traveling to different societies and meeting people. Lots of philosophizing.  

Same universe, dramatic and idealist stories with similar character archetypes. 

Same universe, Space Opera, while Queen Millenia is a long story Galaxy Express is episodic but boths are dramatic and idealist stories about war, racism and distant planets. 

Somehow, when watching Hana no Ko Lunlun, I got reminded of Ginga Tetsudou 999. Both series are about a young person going on a journey, visiting various places in Europe (Lunlun) or in space (Tetsurou). The series are episodic in nature. In every episode, the protagonist arrives at a new place, and sticks his/her nose into the affairs of other people. Doing so, they get to know people of a lot of backgrounds and interact with them. The experiences they make are not always pleasant, but somehow the protagonists make it through all episodes unscathed. Also, both series seem to convey the same message, which is by meeting people with an open mind, and helping them to improve their lives, one can make the world a better place. In both titles, I found the naiveté sometimes awkward, sometimes it made me feel warm and fuzzy inside. If you like a nosy protagonist on a quest for the betterment of humanity, both series may be for you. read more 

Same themes of machines and humanity, how getting our humanity rejected, life will be joyless, but Texhnolyze does it in a very nihilistic way but GT999 does it more in a lighter way i guess. 

Both shows must be very "old" for many anime fans today. They have completely different settings and genres but both take their time to explore the characters and the world around them and have actual progression (Ginga Tetsudo 999 is more episodic, though). Both shows are very tragic and elegic and are centered around an orphan kid who has to fight his way through life. Both mc's get to know a mysterious (fleshed-out) woman who tends to be some kind of mother figure. Ashita no Joe is a bit more hardcore and clearly aimed at adults while Ginga Tetsudo 999 could be enjoyed by children as well. read more 

I'm really surprised noone has mentioned these two before. They are really similar. They're both dealing with philosophical themes concerning death and what it means to be alive, and dealing with consequences of your choices in life. They're both pretty dark and slow-paced animes about a few characters travelling around and discovering their own truth from talking to people they meet along the way. They both also deal with conflicts between robots and humans. 

Space adventuring from one planet to the other in search of a superior universe goddess to grant wishes. Presence of androids with hearts. 

In both anime there's a protagonist going on a journey with specific aim but on his way travelling through various places where he faces different, mostly unusual people and types of society, where they help those who are in trouble. Though Aoi Blink towards the end focuses more on it's adventurous side. Also both main characters are voiced by Masako Nozawa who is also voice of Son Goku/ Son Gohan from Dragon Ball. 

Both feature an intelligent adult with a young companion meeting people and helping them. Both can be very emotional and philosophical.  

Both feature a protagonist who travels and speaks about the sanctity of life. Each are episodic and can be very emotional. 

From the same original creator, the famed Leiji Matsumoto brings his characters to life with his many Space Operas, like Space Battleship Yamato and Galaxy Express 999, which both share rich dramas in space, attractive character designs (even better with the remake of Space Battleship Yamato 2199 over it's original adaption), and laser guns that go pew pew. I highly recommend anything Leiji Matsumoto has worked on, and Space Battleship Yamato 2199 is a good place to start, while his older classic works can be enjoyed later, sort of like enjoying the original Gundam series after, if you've only watched the latest incarnation prior. 

The novel this movie is based on was part of the original inspiration for Galaxy Express 999, and the similarities aren't hard to miss. This movie is much (much, <i>much</i>) heavier on philosophy than GE999 is, however. Don't bother if you have a short attention span; this is one of the slowest-moving, most subtle anime ever. 

Both involve traveling through space, meeting people and having adventures.  

Both Travel into place to place and has Cameo appearances (Tsubasa haves the most and Galaxy Express 999 haves some.) 

Travelling to various planets with intriguing characteristics, changing bodies, and at the end, political schemes. Kaiba is a return to the 60s and 70s in character design and finds inspiration in Galaxy Express 999 in themes. 'What if we could swap bodies?' is a question addressed by both works. Further, the two series have protagonists travelling to different intriguing planets and societies, and both hide underlying political schemes which gain more importance as the episodes go on. In both series, various aspects of dystopian transhumanism in moving scenarios are presented which the protagonists remain silent about, leaving the viewer to ponder.