Epcot has room for possibly 4-6 more countries. Two could easily fit where the outpost is. One between Germany and Italy. One between Japan and Morocco... Lots of room. I love WS and read stuff about this all the time. I would love to see some additional countries added. They would need to be countries that are diverse enough to add something new and also have some architecture that would be related directly to them. Some that I always hope for include:
Russia - Kremlin style main building
Holland - Huge windmill main building
India - Taj Mahal mail building
Brazil - Christ the Redeemer maybe if Disney can get past the religious aspect
Egypt - Sphinx and or a pyramid or two
Greece - Parthenon
Anyway, the truth is that there will probably NEVER be any expansion in the world showcase. It's sad, but anyone who loves and knows Disney knows that everything that is done these days is done to increase profits or increase ticket sales. The inconvenience that the construction would cause, even if it was sponsored and paid for by the new country, wouldn't be offset by the potential increased income. People will visit Disney to see the new fantasy land. People will visit AK to ride Expedition Everest. No one is gonna visit Epcot just to see the Holland pavilion. It's sad, but the monetary incentive just isn't there for Disney to pursue a World Showcase expansion
Sad, because in my opinion, world showcase after dark, when the tribal music is playing and the torches are lit is the most magical place on the whole property. I love just walking around and browsing in and out of the shops at night. The atmosphere is totally different than during the day.