Functionally, Salesforce Essentials checks practically all the boxes you can think of, especially for a small business. Yes, there is extra functionality with more advanced products, but Essentials is nevertheless quite comprehensive in its own right. Probably the biggest constraint is the limited number of users. If your business is in the early stage of development, the maximum 10 users limit is unlikely to be problematic, however. If you decide to upgrade for any reason, doing so is a smooth process.