Being human syfy s.4 is a big disappointment.

[bcislandguy]

The Uk version of being human had the exact same issue, the character development got so stagnant at the end of the series they literally killed them off and straight up replaced the main characters with younger versions to keep the series going without having to retool and relaunch a new series and keep the existing audience. They went as far as almost reversing the 3 main characters personalities to reenergize the series

Vampire went from badboy to this uptight british guy
Ghost went from mousey librarian to sexy hipster girl
Werewolf went from bookworm nerd guy to more streetwise guy