Having watched through all four seasons, I now feel like I have the right to write a review for someone who may be considering picking this anime up for the first time.
I'm not the most experienced anime watcher, so I won't split this anime into all the sections I have been asked to rate but will more give a quick overview and explain why I liked it.
If I had to describe this anime in a word, I would use the word "Simple."
It doesn't have particularly long running arcs or major plots or complex twists and turns. It doesn't make you think in depth about what could happen next as it's relatively predictable and it certainly does not have a complicated romance plot.
However, it's light hearted, easy to follow, enjoyable to watch and it made me smile through it.
So if you are looking for something fun to watch on a rainy day to pick you up, it's worth a shot.