tl;dr- the planned story for R2 had to be scrapped entirely due to the fact that R1 was on a late-night thursday slot and R2 was moved to a prime time Sunday slot, mostly because they couldn't write R2 with the assumption that the audience had seen R1 before. Among other things, the subplots involving Cecile's relationship with Suzaku and Suzaku's connection to Geass (ie why he went catatonic at Kaminejima when the elevator thing activated) were basically dropped, and Rolo was added in.
One should note that this is far from the first time that a show's direction has been influenced by executive meddling, hell, Geass R1 had a lot changed because it was originally slated for a prime time slot and moved to late night, and probably wouldn't have been as good as it wound up being if it weren't for that.
And this is actually a pretty amazing analysis of the situation I just saw posted on /a/:
Rolo is meta as fuck
Rolo is an expression of Taniguchi’s frustration at not being able to develop R2 his way.
Rolo was forced into the story as part of the “re-envisioning” of the show that led to many changes, some of which suck ass. Taniguchi is aware of this. And he is aware of his own situation: forced to work with the damn thing anyway, for the profit of his superiors, no matter how he feels. I’m not making him out to be a great creative mind of a martyr, just noting that he kind of feels a little fucked. Hence, the place of Rolo in the story.
He’s unwanted. Defective. He’s made into what he is because external forces, in this case the Geass cult, decided on it. He does not start out with a will of his own, and his role is to deceive. This is how Taniguchi sees R2: an imperfect creation forced on the viewers, trying too hard to be liked and accepted. No doubt he sees himself as a “disposable rag” at the hands of the executives, and the show as possibly equally forgettable by the viewers. And then, of course, Rolo as the representation of the spirit of R2 kills something that was positive about R1.
So Rolo’s death is both an embodiment of sincerity and deception. On one hand, Rolo accepts his status as a tool but still strives toward what he believes is good in the end. A fairly plain admission by Taniguchi that his work has its failings, that his own capacities are limited, and that in spite of this, he will still try to work around the obstacles and make it good. The very removal of Rolo might even suggest a graudual return to his original plans. But on the other hand, the scene is highly emotionally manipulative, and a decent amount of effort was put into it, in spite of possible dislike for the character. And people seemed to drink it up. That in itself is a fuck-what-you-think-you’re-going-to-watc
Personally I agree with the idea that Taniguchi's been doing his best in spite of being fucked over by the execs, it seems like people are finding out he was pissed off about this a year ago just now and assuming he's still pissed off and has basically been phoning in all of R2 and therefore every story development they disagree with is due to that. I for one like the current R2, and I honestly think Taniguchi and the rest of the team have gotten over what happened and are happy with the R2 they've created.
That said, I'd love to see the original plan for R2 in some way, perhaps as a manga?