The canvas of most wooden flat tops is rotten by the time we find them. These trunks require many hours of hard work to refinish but they're almost always worth the effort. This is an example of having to compromise sometimes between history and beauty. The third trunk above is an example of a true steamer trunk. The name steamer trunk is almost always misused.
Many people tend to generalize and call all old trunks steamer trunks which is incorrect.
A true steamer trunk is about half the height of most regular flat top trunks, the other dimensions are about the same as for a regular flat top. Steamers were used by passengers in their quarters during steamship voyages. Everything they would need during the voyage would be packed in that trunk and it was allowed in their room. Their other trunks, if they had them, were stored in the cargo hold and were not accessible during the journey. So, the term is associated with steam ships but not all trunks that traveled on steamships were steamers.