Whether you choose to categorize and go for a more specific approach such as committing good deeds or bad deeds can create a totally different feel as apposed to just making decisions that would suit your real life personality and/or your actual judgement. Some scenarios would justify killing and some wouldnt, but what the game really offers the player is the ability to choose one such as killing through sheer frustration or becoming the white hearted pardoning king that forgives the arrogant slave in order to gain the favor of the court or the people of albion. Let's imagine a scenarion that would offer a player to choose different roles with plausible consequences to each decision and you guys can reply or comment on these decisions as you like.
Ok, lets imagine ourselves the King on the throne, lets take the more real life approach that POOP described which is making decisions based on your personality in real life or in other words, without second guessing a second decision and going with that gut feeling.
So lets say you have completed the revolution and have many followers that have helped you eliminate the opposing army and overthrow the former tyrant. On your adventure, you will be making promises to your followers in order to gain their favor and have them assist you on your quest to fighting your evil brother. Let's say one of those faction leaders came to your throne and asks you to fulfill your promises. He wants you to give him his northern land which was stripped from him back when the evil brother reigned. That peice of land generates 10% of your entire countries economy (Mines, factories, farms), including taxation etc. Now as Fable has always been, for every decision there is a consequence. You can be evil and toss him into the dungeon, extort as many benefits from his land, his people, and his army to accomidate your evil goals. Hatred, poverty, child labor, discrimination, and an unfair distribution of wealth follows through that decision. However, another option is to be the good trust worthy King, give him the land, gaining his favor in court, the people's gratitude, his loyalty, taxes form his land (will not cover the economic loses from giving him the land in the first place), and his armies will serve your will. You wont have as much money as the previous decision but your story as ruler will most definetly be different. Remember that the environment changes as you make decisions on your throne. If your the evil king thats enforcing the industrial revolution through poverty and child labor, than your land will have factories everywhere, pollution, yellow gasy air, and people with no housing in the streets unable to find food bla bla bla. If your the good king than youll have clean waters, fresh air, your people will be happy and your country flourish into a green landscape with a positive atmosphere, that decision follows with a lot less problems with the people but your wealth will not measure well with the evil king.
You can choose to use your powers oppressively or to enforce justice where needed. So basically, the ultimate question in Fable 3 in my opinion would be, do you as a player care about the consequences of your decisions? and if so, would you rather be the selfish tyrant or the selfless hero?
Remember this is simply a scenarion from my imagination and only serves as my opinion of a king like scenarion in the Fable III game. I believe the game has to be this complex in order to create a realistic feeling towards ruling over albion, otherwise ruling over albion will just be a walk in the park with nothing intense to remember after you complete the game.