Painther,
I am addressing a few concerns that are ought to take place in the near future.
One is the massive development (for any country's size, let alone a country of the size of Qatar) versus its small population, which will cause Qataris to loose even more control over their country than they have already lost;
The other issue is what is going to happen to Qatar right after 2022, when all infrastructures are completed and overbuilt for a country of the size of Qatar;
And finally on the medium term, the need for carbon fuels will decrease (not necessarily the raw material itself) which will lower its price and therefore the income of countries like Qatar.

With a lower income, lower expat and migrant population, massive overdesigned infrastructures, Qatar will face difficulties in just maintaining itself.

A pessimistic view? I would say, one that should be carefully studied by Qatar, now!