Here is my proposal:
No income tax.
Sales tax on legally established businesses.
Definition of legally established business is any entity the government has created distinct from an individual for the purposes of business.
Selling vegetables out of my garden is not a business. That is a personal affair unless and until I take the effort to make the legal distinction between myself as a person and the business. Then, as a fee for creating and maintaining a separate entity, the government takes a sales tax.