While I found the Hammer didn't involve a lot of material in terms of fighting, combat, or other standards of fantasy role playing games, there is still plenty of rich material to mine.
The first thing to review, is base campaign assumptions. In this setting, Gig, the third son of the noble exiled family, has no expectations on him that are standard. If the family was not exiled, he would have been sent off to the priesthood because the eldest stands to inherit, the second is a back up so to speak, and the third... well, he's extra and even historically, they were often sent off to the church. What happens in noble families in the setting you're using? Are they given command of legions that they are no qualified for? Are they made heads of guilds through marriage? Do they form unique organizations like Pathfinders?
In that vein though, what happens with other people? Teuccer, a young lady from the mainland, fresh to the colony island, wants to be a doctor. Back on the mainland, that would never happen because it wasn't a woman's place. In her new home though, while some may consider her eccentric, they trust her abilities and treat her like the specialist she is. In some ways though, this is part of what Dungeons and Dragons has suffered a little from.
I don't want to say that the game is politically correct, but when looking at most eras of history, things are hard for the common man. Slavery is a common occurrence. Strength of law is enforced by actual strength. Women in many instances, are limited in what jobs they can take. They face real social barriers and have real hindrances.
By being so modern in its outlook, Dungeons and Dragons takes away some of that potential struggle. Now if your game is all about going into the dungeons and collecting the loot, that is appropriate. After all, you don't want to make it more difficult for one player than you do another in terms of buying equipment and getting solutions that the other players have.
But if its about role playing struggles and every one is the same and everyone has the same benefits and the same flexibility, then you might want to look at some of the old social limits. This includes something like looking at the wearing of certain colors, the use of weaponry outside of the nobility. One of the ideas that the old d20 Excaliber book mentioned as a role playing bit was that only knights could use swords. This didn't prevent other social status characters from making fighters, but they would be known by others weapons. Indeed, some weapons are distinctively peasant in nature or not meant for the higher ranking soldiers.
Another aspect of the colony life, is whose paying for it? Is there a single organization that pays for the people to move there? To pay for the people to live there? what are the obligations of the people who live there? In The Hammer, the colonist are expected to turn off a certain amount of beef in exchange for the necessary tools for living like nails, hammers, hoes, clothing and other farming tools. The isolation of the setting means that often the characters have to make due with what they have. In this book, there is 'the Company', but we don't find out too much about them in this book. Considering I'm reading another book by the same author called, 'The Company', it wouldn't surprise me if that some how all tied in together.
The Hammer is a book that is filled with characters breaking their standard background roles and fighting against the limitations imposed on them from society. It is worth reading to see how island life might cause innovation among the least likely people.