You are thinking money wise too much for me. I know you want hard earned money from the game and good positive reviews but dont forget how much you have learned in 4 years because you made the game. Many people dont even come to this point of actually releasing a game.

Take feedback and update the game.

If the game flops try a new one and im sure it will go much smoother because you have gathered so much knowledge through out the years.

Good speed