RobiHachi

Both are about a wacky trio experiencing episodic adventures in space and share the same goofy, light hearted atmosphere. Even the way how the antagonists are presented is similar. While RobiHachi is heavily based on silly conversations with local inhabitants for its humor, Space Dandy has a greater variety of set ups thanks to an more action oriented approach. 

Same general sense of crack/brainf*** 

sci-fi and comedy go hand in hand in both of these shows, though I most say that RobiHachi is much more on the comedy side than Kanata no Astra, and Kanata no Astra has a better storyline I guess ( both are comedies in the end and shouldn't be too fixed on the story anyways in my opinion), so in conclusion if you enjoyed the comedy aspect of Kanata no Astra you will definitely enjoy this one  

Both series are very similair but great. Traveling from place to place to achieve their goal. they got really great humor and makes it really fun to watch. being chased by some characters with a exeptional character traid. But overal very similair tastes. You should definitely watch it if you liked the end. 

Both shows have a sci fi setting, with a protagonist who isn't too bright - he acts first and thinks later, which, expectedly, lands him (and his companions) in a host of troubles. Both shows don't take themselves too seriously, which means there's a LOT of silly comedy and humour that's totally out there. The women, too, don't serve much of a purpose in both shows, except for being a big-breasted hardass or being nameless characters. 

They both have very similar vibes and story structure like from point a to b with some fun little detours and delimas and they left me with the same feeling after watching them It felt complete but I still wanted more 

Cute and bright art/aesthetic Friendship and Bromance Both are comedic and have similar character types  

Both are comedies and one of the main leads is an alien. 

While the two series are entirely different story-wise, RobiHachi featuring space exploration while ClassicaLoid features versions of classical composers living together. Yet they both have that colorful completely off the wall humor with the lead characters tossed into totally unexpected scenarios that might or might not involve a giant robot or two. 

>Similar type of comedy and randomness > Simple and bright character designs >Cute mascot characters >RobiHachi has few Binan Koukou references 

Both are set in a future where Earth is populated with aliens. 

It gives off the same comedy vibe. Also, the colours and designs of some characters are very similar to those of Nanbaka.