I think we will quickly find out that designing this project is quite difficult just making the base game. Especially if we want to make it in a way that involves teamwork and robust code. I would shot for a very basic TUI game and move to bigger and better ideas when you get there.
If you want my opinion on what could make this game more interactive would probably be more minigames. Such as an animal attack, hunting, fixing minigame (When your wagon or transport vehicle breaks down), a minigame in towns for gaining money such as a printing press operator, etc. Maybe you could include more interactivity with the party members and your available supplies. Maybe include items you can obtain and use throughout the journey.