Responses
Try these:
http://www.mangago.me/read-manga/merry_checker/
http://www.mangago.me/read-manga/soredemo_kamawanai/
http://www.mangago.me/read-manga/blue_sky_complex/
http://www.mangago.me/read-manga/kimi_to_parade/
http://www.mangago.me/read-manga/mousouka_koi_o_suru/
http://www.mangago.me/read-manga/hare_tokidoki_wakabasou_araara/
Plot wise they are not similar to rutta or akihabara, but these have an adorable simplicity that I feel is similar to those two you gave.
I Want a story similar to both:
Rutta to Kodoma
Akihabara Fall in Love