My first project was a side scroller where movement was simple to handle but complexity was still there.
The example was AUMs Moonwalk article or something like that and the characters were land tanks (the player) and space ships (The enemy).Getting the turret to pan was initially tricky but in the end it all went well. Then I followed thru with the jumping sidescroller (dodge flowers if I remember right).
Next was the Spaceshooter series (3rd person no gravity) and finally an FPS, very simple to initiate but the more interaction required, the more the scripting complexity rose.

They all gave the foundation for the next exercise, then when I had grasped the basics of C_script, they go and change the scripting language again!

A paper trail is a must when starting out at the very least.
You need to know what worked and under what circumstances they worked, how and why they were used and where thier relationship is to everything else, this way you can back track on errors or conflicts and know where you are at.

A paper trail will also give you a tight schedule to work within so that you can finish each test and move on knowing you have your trail covered.

Dont know if its any help or not but there it is.