It was likely because HSI didn't really know what it wanted to be. The first 2 episodes made it like some J/K-drama where a teenage daughter is being bullied by a evil grandmother and fail mother, but then episode 3 hit which was...
. Then it went into slice of life mode (granted it was still superior to K-on and its various clones) till about episode 8, then it became great again (focusing on Ohana and her relationships with other characters, including Ko) and it maintained this till the end of the 1st half (about episode 13). About half of the 2nd cour (episode 14-20ish) was slice of life mode again, then it started to be great again as it was focusing on the financial difficulties of the inn. The ending was also stellar.
TL;DR - It was inconsistent. But despite the inconsistencies, I still very much loved the series, though I was "tsundere" over it for a lack of a better word during its airing - see my various rants on various episode discussion threads.
For some luls, this was my various reactions to different phases of the series:
Ep1-2: Holy cow. New standard to modern slice of life/drama inc (Yes, I thought they were better than even the highly acclaimed Ano Hana which was airing concurrently at the time)
Ep3: FUUUU- *me wants to punch Okada in the face*
Ep4-8: Slice of life mode... zzZZ
Ep9-10: Oh it's getting good now.
Ep11: !!! 11/10!
Ep12-13: Yay solid finish to the first half.
Ep14-16: Filler mode...zzZZ
Ep17: /facepalm + "/minkoface"
Ep18-19: Goddamn it more filler.
Ep20: LOL TRUE TEARS CAMEOS. AUTO 10/10 /fanboy
Ep20-25: Hey, it's getting good again.
Ep26: Wow, what an excellent ending.