Used informally to add another point, especially one that makes an already strong case even stronger.
“It's more spacious and quieter, and on top of that, it's closer to the subway station.”
“The tour includes all meals, and on top of that, it comes with free airport pickup.”
This casual linking phrase fits Task 5's conversational tone better than formal connectors like "furthermore," and it's great for stacking a final, convincing detail onto your argument. Use it near the end of your response for your strongest extra point, right before you state your conclusion.
Synonyms: additionally, plus, besides that