Mine's hard to choose...kinda stuck between Excel Saga and Chrono Crusade, but I'll say Chrono since it's not a load of randomness and brain leakage. Still love Excel XD
That's a hard choice since a lot of the anime I watched was back in like 2010, but some of my favorites were Kurokami, Full Metal Alchemist Brotherhood (even though the original is great in its own right), and The Melancholy of Haruhi Suzumiya.
I'm actually planning on someday rewatching Kurokami and The Melancholy of Haruhi Suzumiya, just to see if it's good as I remember. The thing is, it's hard to say anything about both of them without spoiling something, because while The Melancholy of Haruhi Suzumiya looks like a typical high school slice of life anime, it's a little more than that.
Also, I would say that One Punch Man has been a newer favorite of mine. I like how it parodies over powered character animes like DBZ.