Government of Marshall island is now gearing up for crypto currency as its legal tender. Currently using US Dollar as its main currency , it will be shifting to use cryptos and later this year will have an ICO for its national currency.
A country with 53k population won't be able to help the crypto community in any major way. But it will just increase the number of countries where Cryptocurrency is legal.
Also to your second point, Marshall Island is planning for a Cryptocurrency backed up by USD as it is the official currency of that country. It is very similar to the Venezuela's petro currency. So I don't see any major impact coming to crypto market apart from adding one more country to the list.