The phrase "level out" can be replaced with a variety of synonyms that convey the same meaning. One alternative is "stabilize," which suggests bringing something to a steady state. Another option is "even out," which implies creating a balance or uniformity. "Smooth out" is also an option, indicating the process of removing bumps or rough patches. "Plateau" is a synonym that describes a situation where progress or growth has stalled, but there is not a decline. "Maintain" is another synonym that indicates holding something at a consistent level. Overall, these synonyms for "level out" convey the idea of bringing something to a steady state, balance or plateau.