There are probably three major “knobs” that can be adjusted to control gameplay in AR, as facilitated by the rules anyway: scale, player power, and difficulty. There are also less easily quantified things, including Grit.
Scale can be manipulated in two big ways. The first is just what your group tends to focus on in general, and in that focus uses a smaller scale. In one game, you could be interested in the details of war and battle, and so spend a lot of game time doing that, using a lot of small tasks; leaving other things, like management of the colony, to a few occasional die rolls. You could also do exactly the reverse, focusing entirely on politics, diplomacy and building, and resolving a major battle with one roll.
The overall scale for the whole game–and all situations–can also be adjusted. For instance, you could play a whole game out that dealt only with the first year of a colony’s founding: dealing with most everything in some detail. Alternately, you could work through 300 of history, switching characters along the way, to play out the whole history of the colony from its rise to its fall.
AR gives the potential for more player power than is typical, but a lot of it is not required. Most of this comes down to creation of the background world, modification of it, and the invention of challenges. On one hand, a more traditional game would have the GM responsible for all of that, with the characters only making minor additions to individual scenes, and handling their necessary jobs. On the other hand, the GM could just provide a springboard for the players, coming up with basic ideas but allowing the players to do most of the work. Even more extreme is to use the optional rule of cycling even GM powers with the white stone. Thus no single player ever has more power than anyone else. In general the functional difference between these modes is achieved through player use of Vis, the commonality of propositions and their acceptance, and the GM’s disclosure of his ideas (if there is a GM).
By default, a lot of the tasks in AR will be relatively challenging for characters under normal circumstances. It’s a hard world, and important things are never easy. Unless characters are applying their values or spending Animus, they will fail fairly frequently. This makes building up and conserving Animus critical.
However, things could definitely be throttled back, so that characters would need to worry much less about Animus, and could succeed much more readily. This then makes what the players want to direct their attention towards far more important, since Animus is not longer such limiting factor in getting things done.
On the other hand, you can turn the difficulty up and make the game much more intensely about character drives. With this mode of play, characters who don’t wisely distribute Animus and act in accordance with their values will quickly fade from prominence. They may even become sad stories and be abandoned by the players (which is a perfectly valid thing to do). Only very intense people will be able to keep the Civitas alive.
Grit relates heavily to difficulty but encompasses more than just the mechanical difficulty of tasks. An extremely light, non-gritty game could lead the players to imagine a cartoon-like world, with idealistic characters pursuing their dream in a relatively easy fashion. There may be war and famine, even death, but it doesn’t affect the main characters too much, and the colony continues on. The characters with the most Animus are the shining leaders that make it all possible.
Conversely, a highly gritty game takes the harshness of the time and finds ways to exaggerate them. Everything is hard, and everything has a price. Characters have their ideals, but things rarely turn out very well, and survival is about the best anyone really hopes for. Food is short, enemies are everywhere, and friends die daily. The characters with high Animus are driven, but may still be broken wrecks emotionally, relying on their duties to keep them going.
Of course, like any of the “knobs” there is a continuum here, and most groups will want to play in the middle, and even move along it form session to session, and scene to scene (occasional dark moments breaking up an otherwise idyllic situation perhaps).
AR allows such flexibility, and so there is no single correct way to play. But it’s good to be aware of what kind of game you want – and to make sure everyone you’re playing with wants the same thing.