Much information can be gleaned from these censuses. Just keep in mind that they can have errors in them. Although you may not find many city directories in your local FHC, it seems appropriate to mention them now, after the U.S. Census. If for some reason you cannot find your ancestor on a particular census, and you are fairly certain of the locality, you may want to find them in a city directory. A city directory is like our telephone directories of today, but theirs was more of an address book, used mainly for advertising purposes.
City directories are good, especially for large cities.
One problem though, is jurisdiction. Suburbs are not usually included. The purpose for using a city directory is that it will put your ancestor in a particular place at a particular time. Read the forward in the front and read the first few pages in the front and in the back. You never know what you might find there.