Guild Wars 2

So, we all know very well that because of the fact that we killed Zhaitan, that there is more magic for the other dragons, most importantly Mordremoth, making them more powerful. Does this mean that as we kill each dragon the next ones will be more and more powerful. Leading us to a point when all known dragons are gone, and the mysterious Sea Dragon rises uncontested to really screw things for Tyria. And on that note, what are we going to do once all the Dragons are gone? Will we be able to tap into this larger availability of magic? Thoughts?

Its not like there is more magic for every dragon that dies.

There are only less magic users/customers.

There was a phase where magic was abundant, yet the dragons slept.
Once the dragons are gone its going to be like that again.

To be honest though, I doubt Anet has a world building concept as backround for their future story work.
They will just make it up as they go.
The GW2 story is much more character than world focused/driven anyway.