Interesting post Teuto. In your post you're describing two forms of greed. 'positive' greed and 'bad' greed. I wouldn't put it like that, rather desire/ambition and greed. At it's core those two driving forces are the same but different at the same time. Greed is a state of being where you can never be satisfied, always looking for more. In my opinion greed is always 'bad'.
Ambition/desire on the other hand also drives you to improve but it's easier to balance out with moderation.
What if my ambition never stops?? Is there such a thing as "too much money"? too much power? too much status? what if i don't have that "stop", what if my ambition evolves and keeps increasing?
The line between a person being ambition and a person being greedy is very blurry! What some people call being greedy i call being ambitious!
If you can't set a clear line for yourself your ambition turned into greed. The line won't be the same for everyone but if you don't have one you will never be 100% satisfied thus never truly happy.