hahaha ok, yeah, it's a hard post but everyone has their own tastes. Of the four you mention, I only watched Mirai Nikki and Elfen Lied, the other two I never watched but I know they are very popular and loved by the public.

I liked both of them and I was entertained watching them, not to say that they are the best in the world haha I still don't dare to say that any anime is the best in the world, not even SNK because it's relative to personal tastes 😂

I also usually say "this anime is a gem" but there will be people who don't like it and vice versa, they will tell me "this anime is great" and I don't like it (example: Naruto) so every opinion, negative or positive is valid hahaha