The way Kuvira was dodging all of Korra's attacks was sick. She didn't let one hit land until Korra went into the avatar state which is crazy because she hasn't been billed as a master bender at all...she's just an all around great villain. I definitely think Toph is gonna make another appearance in order to get Korra's mind right.
Varrick's development has been great. He went from just being a rich inventor from the southern air temple tribe, to a key component in the politics of Republic City, to a key character against Kuvira's reign without even appearing in every episode.
I think she was indirectly billed as a master bender though. Look at how much respect Suyin showed Kuvira. You could tell she respected her power, long before Kuvira had an army. Suyin didn't try to stop Kuvira when she said that she was leaving Zaofu and taking her security force. She also didn't try to take her 1 on 1, instead opting to sneak her. The respect for Kuvira's bending has been clear.
Suyin had no problem going 1 on 1 with Lei, but showed Kuvira all the respect in the world. Also, Suyin has repeatedly said that Kuvira was smart and a natural leader.
Plus, this GIF right here is proof of her pure accuracy
To round them all up like that, while they're moving and to not physically harm a single one of them while dodging their attacks is pretty amazing. She didn't waste one movement. Her fighting style is just like her personality. Calm, Cool, Collected, Calculated, And Sharp
Which also foreshadowed that she would sort of take Korra down easily. If she can do that to 10+ moving targets, then Korra's stationary fighting style should be no issue.