Conservation Reserve Enhancement Program Improvement Act of 2023 This bill revises the Conservation Reserve Enhancement Program (CREP), which is a component of the Farm Service Agency's (FSA's) Conservation Reserve Program (CRP). CREP is a public-private partnership program which allows states, tribal governments, and nonprofit and private entities to partner with FSA to implement CRP practices. CRP is a land conservation program that provides an annual rental payment to farmers in exchange for removing environmentally sensitive land from agricultural production and planting species that will improve environmental health and quality. The bill specifies that dryland agricultural uses and grazing are included as appropriate practices under CREP. The bill also allows a land owner or operator to elect to determine the annual payment amount allocated for each year of a CREP agreement, instead of a fixed payment per year for the contract period. For drought and water conservation agreements that include the permanent retirement of water rights, annual payment rates must be equal to the irrigated acre payment rates determined by the Department of Agriculture (USDA). In the case of an agreement that permits dryland agricultural uses, the annual payment rates must be equal to the difference between the irrigated acre payment rates and the dryland acre payment rates determined by USDA. The payment formula is retroactive for certain existing drought and water conservation agreements. Further, the bill exempts CREP payments from the $50,000 annual payment limitation under CRP.