Just adding my two cents here:
I think it really would have helped the story of somebody had actually talked to Ran about how dangerous her relationship with Outarou was. As much as he claimed to love her, he made it very clear to those close to him that he wanted to cage her and keep her to himself, away from her family (look at his attitude with Jin).
The whole arc was almost perfect. I could have done without Outarou's declaration of love at the end. Him wishing Ran to be happy would have been a better ending, maybe regretting not seeing the woman she would become. His scenes with Ran always made me uncomfortable and really felt like grooming when she clearly was uncomfortable with his advances (even if he didn't know her age, he knew she was underage and didn't care that he was touching her inappropriately).
The scenes between Makoto and Ran could have taken more centre stage before the insect arc but apart that it was a lovely ending, seeing Ran finally grow and gain some self-control