I honestly don't know how anyone could rate this anime as anything less than 7. Unless you thought this was an action/romance anime instead of a slice of life, there's no way one could be disappointed in this lighthearted, fun series.
I see Barakamon as one of those animes you watch in between the really intense ones. It's a good break, it has excellent humor, and it leaves you feeling happy inside. The main reason being the main girl, Naru. Naru is a little country-hick kid who befriends a city-dude Seishuu Handa. He's a career driven guy who has no time for fun and games. She's a little girl who's very existence means fun and games. Put the two together, and you get a wonderful comedy with just the right amount touchy-feely emotions.
She teaches him to love life, in a beautiful way. This anime is simple, there's no doubt about that. I feel like the simplicity of it is what makes it so good. That, and Naru. She's hilarious. Seriously man, I laughed a lot watching this. She's also beyond adorable.
Overall 9/10. Give it a chance, you won't be disappointed.