Bitcoin will obviously improve the economy of any country if they have Bitcoin reserves aimed for a long term goal. But as a medium of exchange it won't improve their economy that much because they will spend more than the invested due to price fluctuations.
Depends on how much they are going to start with and what their target is at all.
To get a better picture and to see results, looking at the GDPs of some countries, there is much to be thought about and done..