I'm gonna get a lot of flack for this but..
It's not that those in this community don't have talent, skills, good ideas etc. or never made a large-scale game before. It's that C2 isn't designed for large-scale game development by any means. It's designed with the single hobby developer in mind.
Everything about C2 is internal. The level editor, the event editor, the objects, the animations, the textures, the sounds. It's practically impossible to use C2 in a team and you know what teams offer? Large-scale games.
We don't have massive areas and entire worlds or even (good) tile-based games because you can't use external level editors.
We don't have heavy dialogue,inventories,world-maps,customizable characters, etc. because you can't really use external files. Project files are a temporary workaround at best.
We don't have lots of sound effects and music because you can only import .wav PCM which must then be converted into an unorganized project-bloating super folder of sounds.
We don't have solid, bug-free, ready-to-distribute games because all of that relies on 3rd party software seemingly shoehorned into C2 and forgotten about.
"Oh, well just use a project folder instead!"
Nope. You still have to add everything to your game inside the C2 editor else it's not recognized. So if you're in a team of 5, all building levels - each member will need a C2 license - all of the project's plugins - and the latest build, just to put his or her levels into the game. That applies to *everything*. There's SVN but that sounds like even more of a nightmare and I still don't see how C2 will pick up anything if it is added outside of the editor.
That's not to say it isn't currently possible to make a large-scale game in C2 - I'm working on 2 right now - but it's a dreadful process and I'm not sure we're going to get much farther without a number of changes and additions to C2. I've already had to cancel two others.