Railroad Ink, by Hjalmar Hach and Lorenzo Silva, is a peaceful, puzzly roll-and-write game. You roll dice and use them to build a network of rail and roads, trying to connect the most end-points, fill the centre squares, and make as few mistakes and dead-ends as possible. Like many roll-and-write games, there is no direct player interaction, which (depending on your inclinations) could be a good thing. Also, it scales incredibly well, from a thinky solo game to a gentle group game. This is a very satisfying puzzle game, and the expansion only serves to add nuance to the game.
Good for: fans of roll and write games and railroads; large groups; fans of puzzles.
Bad for: people who want direct player interaction; people who hate neighbours looking over their shoulder.