Your core concept, scope, and mechanics are very well suited to a solo project. The mechanics are relatively simple, but adding small, unexpecting tweaks can be more than enough to make your game stand out without revolutionizing the genre. Now that we're getting into the ladder half of the jam, I think you may benefit from having a more fleshed out production plan so you can more easily split up your work into different deadlines and prioritize different aspects of the game as you iterate.