I always want unique tiles yes 
At first the game is level up mode. So it starts with 4 tiles, after the player levels up it will increase. When all levels are complete it will just be an endless runner.
So at first with only 4 tiles, if I am getting 2-4 of the same exact one it’s really noticable (large tiles so the scenery stands out. it’s not just 200 tiles with random objects where everything kind of looks the same anyway).
Once it’s ‘endless’ I will have ‘zones’ so it will spawn green tiles for a little while and by the time the index of green tiles is empty it will change to an index of red tiles, etc… eventually cycling back to green tiles.