If you are constantly waiting for your houses to give you rent, build more businesses. Not only do businesses give lots of cash, you don’t have to wait long for the money they also don’t increase population.
Another easy way to make your city more efficient is to get rid of roads. Replace them with sidewalks and you’ll be able to crap way more things into your city with the new space you have.
For a more efficient and beautiful city, build decorations in areas with a lot of houses and businesses. they can drastically increase the payout of nearby buildings. and are a smart investment.
*Important* Don’t try to make you city look like Sam’s!!! She is a deceiving woman who get’s everything for free