I have less challenges I can put on myself such as a homeless playthrough. You look back at the first sims 3 trailers about getting into the world, well in the sims 4 it kind of feels like your door is shutting again, even if not fully. In the Sims 4 I rarely leave the area immediately around my house (or my job for the three jobs you can visit in an expansion). I put in way more hours into sims 3, so maybe my current opinion is biased by simply having less time with 4.
