There are plenty of words that can be used as synonyms for "good sums" including, but not limited to, "generous amounts," "impressive quantities," "substantial figures," "significant totals," and "ample sums." These phrases come in handy when describing financial transactions, investments, or simply the amount of something. Phrases such as "healthy numbers" or "plentiful amounts" can also convey similar meanings. It is important to choose the right synonym based on the context of the sentence, and to make sure that it is clear and appropriate to the audience. Ultimately, using a synonym can help to add variety and interest to your writing.