10tacle :
Well PayPal is pretty easy. As far as I can tell, none of these nations are banned from using PayPal. I've been using PayPal for Steam purchases for years as I use it for eBay selling transactions. The only thing I can think of as an obstacle would be a nation's law prohibiting the transfer of money from a bank account to PayPal.
Paypal rips people off on currency exchange rate big time, first when paying and if there are leftover funds when you try to withdraw them.
They will also force upon you a double exchange rate even if you own an account or card in the currency your PayPal account is in just because it doesn't match country you live in.
New currencies being supported by Steam could be potentially beneficial to some countries, because its not a secret that Steam favouritisms some countries while straight rips off others - people using VPS to buy games in "in other countries" because Steam prices are diametrally different there, beyond what could result from simple exchange rates.