"Unprofoundest" is a complex word which means lacking depth or profundity. If you are looking for synonyms to replace this word in a sentence, you can use words such as shallow, superficial, simplistic, basic, or trivial. These words describe something that is not profound or deep in meaning. On the other hand, if you want to describe something that is deep and complex, you can use words like profound, insightful, incisive, or weighty. These words describe something that has a lot of depth and meaning. Choosing the right synonym depends on the context and the intended meaning of your sentence.