Libertine, at least in its written sections, focuses mostly on Final Fantasy VII and not on the Compilation of Final Fantasy VII. This is because I created this website before Advent Children was released and waaay before I got the chance to view it, and because I happen to just like Final Fantasy VII more.
However, I'm not going to deny that Advent Children made a lot of people Reno fans that weren't before. I'm also not going to deny that there are some differences between the way he's portrayed in the compilation and the way he is in the game. But I'm also not going to deny that both these portrayals are canon, so let's get ourselves a reconciling.
First of all, compilation!Reno and FF7!Reno just look different. Yeah, it's pretty easy to write that off to the considerable prettification of polygons in the last decade, but there's a difference in the way the characters carry themselves. I'm gonna stick the official artwork in the chronological order they take place in-universe.
See, notice how he's acting goofy in two of these shots but in the middle one he looks like he wouldn't mind killing you. He's crunched forward instead of being easy and open. In Final Fantasy VII, his body language is just different-- he slouches, he's way skinnier, and he's not smiling. (Also his eyes are a different color, but that's true across the whole damned compilation.) What's going on here?
The fact is, that Reno in Final Fantasy VII is pretty much a bad guy, and Reno in the movie is pretty much a good guy. That Reno was Not a Very Nice Person can't really be disputed- he dropped the plate on sector 7, killing thousands of people, many of them babies, and he didn't seem too sorry at the time. Even if you're under orders, it's a hard thing to ignore. And he didn't seem too sorry at the time.
Reno: You're too late. Once I push this button...
RENO pushes button, children and puppies die
That's all, folks! Mission accomplished.
But here's the thing: Final Fantasy VII takes place in the world's darkest day. The thing that makes Shin-Ra a compelling villain is that at the end of it they're a bunch of people who've made a whole lot of mistakes, overstepped their bounds, and completely screwed over the planet.
But here's the thing: they're all human, and they can feel sorry for what they've done once the consequences come at them like a giant space-rock piloted by an egomaniac with really shiny hair. And I'm not so callous to deny any redemption for those who are seeking it, and though I have my doubts about Rufus and his reformation, he does seem to have seen the errors of his ways. It'd be hard for someone with any shred of humanity not to see what a dark place the world went to during the events of the game. And you know, if the world was destroyed, Rufus would lose all his money. That's a motivation I can believe!
On to the Turks themselves. I really don't believe Shin-Ra was always evil- I strongly feel the JENOVA project and Professor Hojo coupled with Rufus's machinations caused evil to grow where there was once simple captialism. Vincent is a prime example, although he's a former Turk and has some Serious Issues, he's never presented as a bad guy. In fact, compilation material states that he has a kind and trusting nature, and that he was only a sort of guard for the JENOVA project, not it's perfect assassin. And plenty of good guys, including Cloud himself, were once a part of Shin-Ra.
Furthermore, the compilation has done its best to suggest the Turks once served a much less heinous purpose. Reno in Before Crisis is shown to suffer some moral qualms, and is uneasy that his job now involves much more foul play. This is even expressed in Final Fantasy VII to some degree.
Rude: Well if you know, then this won't take long. It's difficult to explain what the Turks do...
Cloud: Kidnapping, right?
Rude: To put it negatively... you could say that. ...But, that's not all there is to it, anymore.
So, given that Rufus has quit the ways of evil, it makes some sense the Turks would become a lot lighter, and more goofy. Keep in mind that the Turks are in fact comic relief in the game. Think back. We're introduced to Reno with that flower scene. We see him bugging the rest of the Turks about their love interests. The Turks in Final Fantasy VII are an odd mix of absolute failure (fight them recently?), comic relief, and total badassery. In Advent Children they just emphasize the first two at expense of the latter. But he still has his moments. That scene at the end with the bomb? Hell yes.