If you're looking for anime similar to Arigatou: Kokoro no Bara, you might like these titles.
The official music video for Kanashiki Mongoose by Seiji Tanaka that was featured on NHK's Minna no Uta program.
The official music video for Aki Monogatari by Kiyohiko Ozaki that was featured on NHK's Minna no Uta program.