For those of you who've seen 11, do find the portrayal of the Romulans refreshing (passionate, emotional, and very evil)sort of like the anti-Vulcan. Or, do you prefer the the cool,calculating, and aloof race as presented by DS9 and TNG.
I'm actually unhappy at both portrayals. I think they've missed the boat on really fleshing out the Rommies to be real characters
and compelling archetypes in the Trek alien mold.
The Rommies in the TV series were always frustratingly underdeveloped. I never really got a good read on who they were. Abrams' movie didn't improve the situation, just muddled it. His Rommies didn't seem convincingly alien at all. They were just humans with funny foreheads. They'd been wronged. They wanted revenge. They cracked some jokes. How exactly are they
aliens?
Humans - or any other Trek alien species - could have stepped right into their shoes and nothing would have been different. All important Trek aliens must be unique and never interchangeable. When there are Vulcans in a story, they should have to be Vulcans or the story changes. Ditto for Klingons, etc.
The key to Romulans is understanding Vulcans. They both have the same problem - emotions that are stronger and more violent than humans. So how do they manage to have a functioning society at all? Obviously they must have come upon some kind of accommodation long ago. For Vulcans, it's making a fetish of repression and logic. For Rommies, it must be something else, perhaps linked to their secrecy and xenophobia. There's some reason that they hide their true selves especially around outsiders. This is the aspect of their species that needs to be explored so that they will not only seem like "real" characters but also not just humans with funny foreheads.
And that is why Nero's joke-cracking and overall loose attitude felt wrong to me. He's not being repressed and secretive enough for a Rommie. But to know exactly why that was "wrong" - and it only felt wrong at gut level - I'd have to know what the larger plan is for the Rommies, for finally fleshing out exactly who they are. There is no plan, and that's the problem.
For that matter, I dislike the idea that all members of an alien species should act the same (though apparently many other people don't share this idea - see frequent complaints such as that character XY, for instance, "does not act like a Vulcan".

).
It's a tricky balance to achieve. They must act "alien" (and limited to a certain behavioral range) enough that we accept them as a coherent alien species and not just humans with funny foreheads. But they must act individual enough that they can serve as believable, "real" characters in a story. They cannot just be "types."
The right way to do it: Garak, Damar, Dukat. All Cardassians, all believable as members of the same species and
not humans, yet all distinct from one another as individuals. Add in the minor Cardies we met along the way, and you have a wonderfully believable portrait of a whole species, constructed from maybe a dozen characters in total. That's what the Romulans need.