I think the sort of slow start is beneficial to the overall pacing. It really feels like a revolution built on the unprecedented small victories of an in-over-his-head charismatic dumb guy. Kamina's not a great character, but I think it's believable the way he inspired a population of resistance fighters who had nearly been ground out of existence and turned them into the kind of organization which was willing and able to develop an actual government.

It's important for Kamina to be this ridiculous sacrificial lamb that the others follow into a situation that they don't know how to handle, before the whole plot about a dysfunctional government without its figurehead trying to stay united against an existential threat can go anywhere. If they hadn't been dragged out of the muck by Kamina, learning how they all (very poorly) manage the post-war government without him wouldn't be as interesting. Kamina is a 'perfect' (as far as the history books are concerned) leader that everyone has to strive to live up to. Because he never had to take on the challenge of managing a developed society (which he, too, would no doubt have failed miserably at) he gets to live on as this deified eternal leader who both inspires and demoralizes those who come after him. There's a simultaneous feeling that "I have to do this because Kamina would have" and "I can't do this because I'm not Kamina" that I think is made all the more interesting by how much of a dysfunctional loser Kamina was. A guy with practically no positive traits who got himself killed through his own bad decisions when his people still needed him was, somehow, the inspiring leader they all needed to make something of themselves.