3. Paragade
The morality system of the series is one of the more interesting aspects, with each decision being divided into each category. The more you do one, the more interesting the chain gets with having the ability to do more in that category. It often comes down to whether a player is doing a "Paragon or renegade playthrough" as to which choices to take. Playing like that means you get to experience all the moments the game offers. Which characters live or die and how that affects the end game (spoilers: not at all) is a great reason to keep playing, and is all controlled by the morality system. The inclusion of interrupts doesn't hurt either.