I must say that I generally liked this second season more than the first and these are my reasons:
1. The female character had a good development in this season, while in the first one she was always closed to what she thought was "right" without overcoming her traumas.
2. The male characters also grew and in this season we get two totally different male protagonists.
3. I feel that the female protagonist stayed with who was the best option for her, since that character grew along with her.

4. Also the change from school to a life outside of it, makes the drama itself should be more mature and I think people were expecting something more of school and it is something that could not be given by the context.
Overall it had a good closure in all the plots it proposed.

NOTE: Can you imagine a series of suspense with the theme of love alarm, it would be good because although it does not touch the subject talks about the extent to which the app tells you that only likes you or that person is obsessed with you.

SPOILER

5. While it didn't stay with who most people wanted, I think it's still a good kdrama, since as I said before there was a better character development, the story is not dramatic, but still intriguing a bit.