Also Natsu, Gray, Lucy, Freed, Bixlow, Levy, Cana, Juvia, and Elfman.

Juvia!!!!!!!!!!!

I don't understand why some of them are a choice here, but really Juvia? Why? She failed at the first test!
I do really think that Cana should have been the Next S class, even if she annoyed me kind of much during that arc.
She has really been there for so long and given everything she've got, so I believe that she would have made a good next S class.

Gajeel because he's strong and awesome :)

Juvia IS powerful. And what if she failed a test? Everyone fails, right? No one is perfect. She used to be an S-Class mage of her previous guild. She's by far the best Water mage. Also, if it weren't for her 'love' when she fought Gray, she'd pretty much beat him.
Anyways, other members who deserved to get promoted are Gajeel, Freed, Natsu and Gray.

SummerThunder, Yeah everyone fails sometimes but that's what makes people stronger. Yeah Juvia is a strong in her previous Guild but she lost to Erza since nobody can beat Erza except Jellal. Well some people are held back by some emotions to fight.

I agree that the four also should have became S-Class wizards also Cana and Bickslow.

she actually had a reason

Definitely Natsu! And Gajeel, Wendy, Gray, Juvia, and Freed. But Natsu is and always will be first!!!! <3

Definitely after what she displayed against Meredy and bearing in mind she was indeed a member of the element four. It's a shame really because Juvia is rarely shown to be that powerful whereas the other 'elemental mages' (Natsu: Fire, Laxus: Thunder, Wendy: Air and Gray: Ice) all are shown to be very powerful.

A close second is definitely Gray and Gajeel and then third Natsu, only because he didn't seem 'mature' enough and was too reckless at that time to be S-Class. Although Gildarts does tend to go blowing holes in walls and accidentally leveled an entire village once. Haha.

Lucy I feel was nowhere near powerful enough then to be S-Class.