The phrase "whole thing" can be easily replaced with a variety of synonyms that convey similar meanings. Some alternatives include "entirety," "totality," "all-encompassing," "complete package," "full picture," "big picture," "total package," "overall entity," "comprehensive unit," "full scope," "integrated entity," "complete entity," "integral entity," and "complete system." Each of these phrases serves as a substitute for "whole thing" and communicates the same idea of something being complete, comprehensive and inclusive of all components. It's useful to have these synonyms handy when you want to add variety and clarity to your writing.