If you have ever played a game, I believe everyone here did.. What did make you wanna play the game you have seen [what you've seen in screenshots or videos] and what has excited you in that game when you actually played it? [eg. unique level system, potions, fancy swords, atmosphere, HUD etc.]
Make your game have a good protection (from hack) because from my expierence as a gamer also a hacker
when I just hack the game kinda changing money value or else..3 days later I quit...
The Important thing is that the gamer can work harder collecting the money for new UPGRADE and new Level and new PLACE to explore or FOR A HARD STAGE such as big Boss.. That`s my opinion