Add a small chance to randomize a populations preferred Luxury after boosting, increasing each time the chance does not occur.


Also probably increase the cost of Luxury boosting by, cause honestly it's not that difficult to get <50 of a given Luxury.


By adding a chance for the Luxury to change, players will be able to buy a greater variety of Luxuries, preventing them from simply cornering one or two markets and forgetting about the rest all game; by making that chance small, but increase with each use, somewhat reliable market trends will form for players to follow.


The player could find out about the new Luxury when it arrives, or be told what the next Luxury will be to predict the trend using a Tooltip.