 If you liked Gintama |  ...then you might like Arakawa Under the Bridge |
Both series has a stylistic way of storytelling and humor. In particular, we have a main male protagonist who we learn a lot about through his relationship with others in both series. There's also a variety of themes explored in both series with an intention to entertain and humor. It succeeds in doing both through its delivery of gags and conversations. In retrospect, I recommend both series for anyone who is interested in a series with refreshing humor.