The villainous A.I known as A.I.D.A. Even if she ended up being a composite with Madame Hydra.

Coulson

It's always been Phil.

Pretty much members of the AOS team- Phil Coulson, Melinda May, and Fitzsimmons.

I'm 100% with you. Lewis Wilson was an excellent character overall.

Coulson, Melinda May, Leo Fitz, Jemma Simmons, Grant Ward, Deke Shaw, Lincoln Campbell, Aida

Those are the only ones that comes to mind

I know there are others that I liked

Yo-Yo wasn't invented by the show actually.

Darcy