Ihatov Gensou: Kenji no Haru

Both are about cat characters and both feature a pair of siblings as the main characters. Both of these are also short and can be watched in under an hour. 

Both are excellent movies that deal with animal main characters who only want peace after their times of serving in the war. They are both very contemplative in their themes and heavily focus on both people and nature. Both are very peaceful movies that have a very strong hold on realism, and both contain surrealistic elements. Would definitely recommend one if you've liked the other! 

What do we hear dozens of times in Bungaku Shoujo? Kampanella, Galaxy railroads, yellow tomato... Yes, the main theme of the movie's plot based on Kenji Miyazawa's books. In chaos and Spring you can see the life of this man, his unordinary point off view on very ordinary things that we never see. Also, in my opinion, the atmosphere of this movies have something similar - lyrical, touching... dreamy. Enjoy. 

Spring and Chaos is based off of Kenji Miyazawa life, while Night on the Galactic Railroad is based off of one of his works. Both films feature lots of symbolism though out. Also both have a lot of surreal landscapes and moments.