Hi, this is my first attempt to organize a game project as far as design is concerned. So as a background I am a beginner at this. My question is about how to judge the size of a game in terms of locations in the game as well as predicting the playable length. Also, how to use this information to actually plan the game.

So the specific game I am referring to is a game type. It would be an adventure. A single scene would usually be a background image with animated sprites, where you can explore the scene and click on exits or entries to go to other scenes. Something similar to traditional Sierra style point and click games, but no real plan to have a player character. So more so first person view. There are many Hidden Object Games with this type of playable element. I really like that idea, but hidden object games are more in-tune to the actual puzzle element as a focus. I would stay closer to the story element instead. Kind of an inverse on the same.

So just by knowing that this is the "type" of game. How could I incorporate into the design phase, the scale I would want. Time is not a factor in this. I could easily say I need 12 key scenes because perhaps I am using the rule of thirds as in film making. So I might have a long beginning with 4 scenes, a longer middle with 6 scenes and a short ending with 2 scenes. Using this concept as a rough idea is simple, but now how can I incorporate timing into this. How many hours of play perhaps in total. I thought perhaps the testing phase would do this. Some play testers return results of their game-play eventually, but this would be too far into the design. The eventual play test would need to be a complete game which defeats the purpose of initial planning. Another idea might be to do this in sections or blocks of time. This would mean early play testing. If I am the developer and know exactly what to do, then I would need external help to do this. That is not something I'm considering, so I am looking for a more drawn out outline to start with.

I guess the best way to rephrase my question would be to say, "What design plans are out there on this type of game and what examples can I look at or use as a guideline". Have you done something like this? Could you perhaps share some insight on this? Or can anyone point me to an example design that is fairly thorough out there. So I don't have to resort to too much reverse engineering of success stories and failures.

I have to ask this because I am not a formal student in game design and I am only now planning a serious project. Any advice about this would be great.