Colorful Harvest wasn't disappointing, but that's because it didn't give me something to expect out of it since the beginning.
The story is just too simple for a non-H manga. The characters are too flat from the get-go and unfortunately didn't improve for the short 9 chapters it has. Some characters suddenly disappeared without a trace. Even if they didn't leave an impression on me, I was still saddened by their lack of closure. The only thing this manga excels at is on its artwork. It's clean but not impressive or alluring.
All in all, Colorful Harvest is something you must read if you want to
bump up your mangalist. Outside of that, you're better off to read something at least half decent.