game-editor.com

The trick to making a great game FAST is to delegate aspects of the games design to specialised programmer/designers.

Project Manager
Researches games that are similar
Decides on overall theme for game
Decides on game feature set
Designs an objectives list for remaining crew
Works out how much people get payed
Makes coffee
Manages the project through until completion

Game Behaviour
Works with GE. Sets it up so that the game starts, stops and behaves correctly. What monsters come out when and why. Has access to data provided by...

Graphics Dept
2D/3D graphics designer(s) supplies and edits bitmaps in games data folder.

Audio Dept
Sound designer(s) who supply and edit wavs in the games data folder.

If you try to do it all yourself are more likely to not ever get it done. There is far too much work for one person to do.