"More piggyback" is a phrase that can be used to indicate that someone is already carrying a heavy load and needs to add even more to it. Synonyms for this phrase could include "burdened," "weighed down," "overwhelmed," or "encumbered." Additionally, the phrase "more piggyback" could also be replaced with "further strain," "additional responsibility," or "additional pressure." These synonyms accurately convey the idea that someone is already struggling to handle a certain amount, but is being asked to take on even more. By using alternative phrases and words, you can vary your vocabulary and better express the nuances of situations where someone is being overloaded.