Early builds of The Sims, dating back to the mid-1990s, were extremely rudimentary. They had a lot in common with the flagship Simcity game of the time. Early interviews with Will Wright about the topic indicate that The Sims may have actually started as an addon for Simcity 2000. The screenshot to the left is one of the earliest screenshots that we have. 

As you've likely heard before, The Sims did start out primarily as a architectural simulator. You can definitely see that reflected in the earliest screenshots of the game. While there were many things about the game that did change, you can see in the image to the right that some assets did make it relatively unchanged all the way to release.