I really enjoyed playing this game after I bought it a few days ago. As I was playing with my friends, I start to realize it would add more purpose to building a house on your raft if you can have a open sea type of online game.
What I mean by that is that it would be so cool if they can expand the game to making it so that there are more people than you and your friends. You can either choose to go online or play a lobby like you do now with your friends. But if you go online. there's a chance while sailing in the seas you will meet with other players and their friends. When you do, you will have the freedom to do whatever you want with them (ie. socialize, trade, raid and start a raft war, etc). It would add a lot more dynamic to the gameplay and it would also make people build forts and defenses to safeguard their crates and other goods the enemy players can steal.
Furthermore, if this would be possible, joining an online server would allow you to start a new raft game and you can invite party members for them to co-create your fortress.
I'm making this suggestion to make the game more interesting and competitive, feedback or adding onto the idea would be much appreciated.