True, however I (and many others probably) would not like the books if they became all about Cato. With the books set in Britain they were both doing the same amount of work together, and now it seems they are going their different ways. We can already see that Cato will probably become an equestrian and marry Julia, but what will become of Macro? He has no political sense and he is only a soldier. So while Cato advances through the ranks, it is obvious that Macro will stay where he is, and possibly go down a promotion from Prefect if he rejoins the legions after staying with the auxiliaries for so long. For example, Gladiator was placed solely on Cato. They had Cato to get the reinforcements, and Cato to rescue the grain ships while Macro was a prisoner. I know they did that to show that Cato is independent, I think that future books will be like this, where Macro gets a second place to Cato.
And although Macro is happy with it, I would rather that didn't happen. Macro and Cato need to be on equal footing, and not one towering over the other.