First Android Game

This is our first game published on Google Play. You are a thief in the game, you need to find the gold objects in the villages and castles and steal them. If you do enough robbery, you can reach the chest and move on to the next level. There is also a store to use the money you earn and it is easier to get various special powers and pass the level because there is a guardian who is chasing you and villagers who inform your place. What kind of way should be followed to advance this game and differentiate the levels more the difficulty increases, the pots add a little variety, but what do you think can change apart from the level design