You can leave it empty first. This hero push is sometimes useful. There may be four stars in the future.

You can be greedy for bullies, greedy for soldiers and so on. But only when you need extra stamps. If there is nothing to spare, put on some 2-star seals (easy to change).

Three-star heroes usually decide what seal to wear after deciding the competitive combination. It's really not Li Zicheng's turn to push the map.