I didn't do much in Gather Up today, so instead I'm going to talk a little about *drumroll* developmental process. One I've been using since I started making Flash Games solo over a year ago. If I liked to coin redundant terminology I would call it something like "The 2 T's". The Toy (the fun part of the game) and the Tech (unique features that the Toy depends on).
Right after conceptualisation (Hey! A platform game with levelling would be fun) the first two things I identify are The Two T's. For level up, the tech was the platforming engine. I spent about a week familiarising myself with Flixel and seeing what it could do. How tool chains would have to be set up and stuff like that. During this time I also started working on the toy.
The Toy is the part of your game, that no matter what HAS to be fun. It's especially important in a game where you are taking risks or you have some kind of message to get across. A well designed Toy, that makes the heart of your game fun, will save you against a lot of poor decision making down the road and makes the game easier to market. It's not to be mistaken with the 'main feature' as it isn't always the focus of the game. Just the moment to moment behind the scenes 'fun generator'.
To give a few examples of this. In Assassins Creed the toy was free running. However dull the rest of the game was, care an attention had been placed into the free running to make it fun no matter what. In Spore the toy was the various editors, the game itself was dull and repetitive in so many places, but the fun of being able to edit everything made it survivable.
In Level Up the 'Toy' was exploration. When I let people loose on the simple platformer prototype I had put together they mentioned a few things, that gems where fun to collect and that they enjoyed exploring the level. The 'Toy' in Level Up, thus became exploration. The level would be big and detailed with a wide variety of locations to visit. The breadcrumb trail of gems would give initial motivation to explore and give significant reason to level and reach even more areas of the map.
If a project fails at this hurdle, it gets scrapped. No second chances. You can develop a fun toy in about two days flat in flash so there isn't any point in trying to jam something into working when you could start over. If it passes the fun test at this point, then I turn back to tech and look at what I need to enhance the fun. Exploration is great but what this game needs is some background and character, so the need for Cut scene/Event handling tech is born.
The important thing here is I've now secured the safety of the new tech I'm working on with the fun toy I've developed than ensures the project is going to hit off.
In Gather Up, the first line of tech was handling multiple areas (I already have the engine from Level Up, so I don't need to worry about that). I knew it was a game that was going be bigger and have more environments than Level Up, so it needed area transitions. The Toy is the gun combat. Fluid movement between exploring and fighting. Focus on movement rather than aim. With the auto aim and jump the game stops being so much about how good your aim is and more about how good your reactions are and your strategy in battle which is why I developed the fighting core first. This makes the guns the tech that is need to support this toy and give it some depth.
In my opinion you can make a game about ANYTHING as long as your toy is good. You could make a game about things as dull as being a waitress or an amoeba. You can even get away with injecting some meaning into them without totally alienating players.