If you've read any bit of honey at all, Onise is kinda like miyamura. onise is suppose to be a bad guy by turns out he's not. Well in a kinda similar way miyamura kun is known as the good guy but has like a bad guy look under the disguise. I think it's similar! I definitely think so I love them both.
Both deal with the difference between public appearance and inner self, and characters opening up due to a relationship. Especially in regards to the male lead, who has a negative image but is actually the opposite of how people see him. Both are light hearted romances, while Horimiya has more comedy and a wider cast, and both explore romance beyond the point of the main characters getting together. While they're focused on the main couple, the friendships are a strong force in the story and the character's interactions are interesting.
Both manga have similar art styles and two main girls whom are a bit alike. (although the main female in Honey seems a bit less.. you know.)
They are both school romance stories with a bit of comedy and a good amount of interesting situations.
These are two very sweet shoujo love stories, both featuring a slightly corny school-based plot. They also have a cute, kind-hearted bishie love interests that looks like a delinquent. While Rensou Mode is much more shallow and comedy-based (but still cute), Honey is adorable and pure, and developing well at this point. Rensou Mode is a oneshot (meaning less development); Honey is an ongoing manga that came from a oneshot called Sugar/Granulated Sugar.
Similar premise, both males who look scary confessing to a girl who is scared of them. Kare to Watashi has borderline smut scenes though, while Honey carries a lighter tone. Both are good reads but stay away if your preferences don't involve smut.