Karneval (TV), Gatchaman Crowds Recommendations
Both involve people with special abilities and secret organizations going after evil elements. Both have characters with very optimistic and artistic personalities. Both have the same action genre and the art of both anime are a bit too fancy.
One has an extra supernatural, comedy genre and a yaoi element in it, while the other has sci-fi and school as its extra genre. One has an extra ecchi element, while one doesn't. The MC in one anime is boy who's more like a damsel-in-distress, while the other anime also stars a boy but he however, can kick ass.
In terms of similairites, both Karneval and Gatchaman Crowds involves an organization who has a goal of protecting its people. These individuals belonging to the organization are skilled users who are able to use supernatural abilities to fight off foes. Thus, expect action in both series.
Among other things, both series employs a mysterious like vibe with the antagonists and backgrounds. Then, there's the main protagonists who seems to be cheerful although they are often curious about the world around them.
Both involves secret organization whose mission is to go after evil entities, except one is gay while the other seems to be cool.
The same intense action and mystery genre, where it involves a secret organization that dedicated in fighting evil and members with special capabilities. The differences are; one has an extra supernatural genre while the other has sci-fi, the protagonists in one anime are up against and evil organization, while the other one are only up against one very powerful alien.