When it comes to finding synonyms for the word "over-built," there are several options available. One common alternative is the phrase "overdeveloped," which conveys a similar sense that something has been constructed or expanded beyond what is reasonable or necessary. Other possibilities include "excessive," "unnecessary," "superfluous," and "redundant." Depending on the context, words like "bloated," "wasteful," or "extravagant" might also be appropriate. Ultimately, the best synonym to use will depend on the specific situation and the desired tone or emphasis of the speaker or writer.