I have 8 years of Lua development experience.
I have created full games with lua using the Love2D framework, created scripts for media platforms in lua such as MonaServer, created scripts for use with lua bindings in C++ projects, as well as created various game-related scripts for a source engine mod.
With this experience Lua has become my most fluent language which makes me very familiar with lua optimization and gives me the ability to clean it up very easily.
I cannot propose proper milestones without understanding more about the project.