I see your point actually, I had a lot's of fun in Garry's Mod too playing people's creation.

My previous comment was more like a personal regret on my self that I failed to convert my modding experience into actual skill in game design/programming. I started it too late for me to relearn all the math and etc. I imagine my career will be a lot different if I started with the intention of designing an actual game.

Yeah, that's all :)