I know the Sims themselves have come on in leaps and bounds since Sims 1 but, imo, Sims 1 holds up very well against the later games.
The decor and furniture still look very acceptable to me and the darker colour of the grass is something I wish had been carried over into Sims 2 and Sims 3. I always thought it added to the darkness of Sims 1, a slight hint of the menace that used to manifest itself when the creators decided to be humourous :mrgreen:
I could happily play with Sims 2 sims in the Sim 1 world if only it was open and had the Sims 2 or 3 camera.