I like Bana, but Nero, as presented in the film, is pretty 2 dimensional.
The thing is, the Trek movies prior to FC were never about the villian.
TMP the "villian" was a giant space probe come to meet and join with its creater. Which it does, in an ultimately peaceful and mutually agreed upon way. The "danger" is incidental, like a force of nature, not directed.
TWOK is the most villian driven TOS film, but the villian and the hero never even meet face to face - it's more about the themes of ageing, loss, revenge....
TSF has Kruge, but the Enterprise crew doesn't even meet him until an hour into the movie and he's easily dispatched by Kirk with a boot in the face. He's not the driving force behind the movie, he is the B plot.
TVH has a probe looking for whales, not trying to destroy Earth. It's at the very start of the movie and the very end. It finds whales, it leaves. Like TMP it isn't a villian, but another "force of nature" .
TFF has Sybok as a villian in the beginning but even Kirk, who is not under his spell, sides with him in the end and they adventure together looking for God. And then fight a growly bearded special effect for ten minutes.
TUC has the conspiracy, a Co - ordinated group of extremist political opponents of which Chang is the face to Kirk and Co, but he's not really key until the final fight. The rest of the movie is political manuvering and a jail break, of which we hardly see Chang in. The movies about the end of Spaces cold war, not fighting a bad guy.
GEN has Malcolm McDowell, and he is the driving force, but really he's just an excuse to get Kirk and Picard to team up.
It's not until FC with the Borg Queen that defeating the villian is the entire point of the movie. Something that repeats in all the movies following.