Suzuku would be a slightly more interesting character if he had a real reason to fight for Britania. The way he's panning out, he's just weak, and fighting for Britania is the easiest thing for him. If, in the second season, he gets a spine, I might find him more interesting. When he's collected, though, he's a decent, carring character. If only his motives weren't all screwed up.
On the topic of Nina, I might say that I seriously pity that poor girl. I don't think she is naturally a lesbian; however, the problems associated with her girl crush were certainly foreseeable. This is actually something that does happen with girls quite often; although they are otherwise straight, they somtimes develop a crush or fall in love with another girl. Don't ask me for details, or why this happens
As for C.C., I'm not entirely sure, but, as I've stated, I don't really like her. I've always found the mystical girl types annoying, though I must admit that she is at least not helpless. Her attitude and honesty make her memorable, but, IMO, not adorable. I'd much rather see her end up as Lulouch's confidante or advisor, since I think she is much better suited for that. I think I'm going to shut up on this topic before I make myself look like too much of a fool.
As for Lulouch, I think he's really awesome when he is calm and collected. I like his control and his incredible intellect, as well as his down to earth attitude. (his goals may not be down to earth, but his attitude/methods are). That said, the new, agsty Lulu is just annoying. He's completely lost his demeanor, and is acting erratically. Overall, though, his character is great.