I acutally like the apartment visitors and the noise. I'ts realistic and it makes me feel like I'm more connected to the environment. Sims usually exist in a bubble, so the deeper integration in apartments is a welcome addition by me.
However, I'd love to be able to build my own apartments. Also, since apartments are stacked in reality, I don't understand why we have such few apartments per building available to use. We should have instead of 2-3 per building something like 8-12 and to view them you just click the up and down arrow like you do to see different floors. They could all be identical, which is realistic too, and we can decorate them, anyway.
Also, for those who want quiet, does the game still put people in neighboring apartments if you untick 'fill empty houses' in the game settings?