In order to create communities, you really want smaller servers. The more often you see the same person, the more often you recognize a name, the bigger sense of community you will have. You don't even have to interact with people, but just recognizing those names on a daily basis goes a long way. The more anonymous, the more random, you interject into that time you are playing, the more foreign you will feel.
The vast majority of people play online games without ever going to forums, websites, reddit or whatever. They just come home and log into a game, so any community building that happens, has to happen in game. Unless you can train the vast majority of players to live the game on their mobile phones, on the web, and then at home in game, you really need to focus on bringing people together. This means that larger communities won't really form for the vast majority of people since global servers have to rely on out-of-game resources to form pools of people.
To your second point, that's just personal preference really. If you want a slower pace game, that's your prerogative. I know from personal experience that I chat all day playing these games in mumble/skype. I have no desire to go back to the day where all I do is type into a chat box while playing.
1) In EQ I played in a so called European guild (conveniently called 'Europa') but we had a good mix of North and South American, European, Mid and Far East players. It worked well, but the segregation of US/EU/AS servers introduced by WoW
killedthat concept. I still don't understand why that model was adopted in the MMO sector.
Because of the slightly higher ping when you have an ocean between you and the server? It's an MMO, not a FPS game. 50ms extra ping is totally irrelevant.
Because of the language barriers? Maybe that was 'solved' for US server since they didn't have to interact with foreigners anymore (except random Mexicans). But EU servers still are a very mixed bag of cultures and languages, and Aussie players are put on Asian servers, so same "problem" for them. I put problem in quotes because it's not a problem at all. You interact with people you can talk to, the fact that there is a faction on the same server that you can not talk to does not diminish your opportunity to find people you can communicate and play with.
2) I disagree with the player name recognition as a trigger to form a community. There is a name recognition aspect, but it's on a guild name level. When I'm in game at a hub, I'll initially start recognizing guild names, not player names. Having a server with a population of 100K players or 1 million players (factor 10 difference) barely has any influence on getting familiar with guild names.
On getting familiar with individuals, that happens when you get into a pick up group and remember a guy because he was a good, cool or just funny player. So you add him to your friends list. From then on, it does not matter at all how huge your server is, you can always find your new buddy in an instant. The larger your server, the bigger the pool of cool guys is, while finding them is not affected. Big server > small server.
3) I don't like voice chat as a primary means of communication in an MMO. Part of that is me: I'm just a bit too introvert to start talking to strangers. Part of that is the language barrier: while my English is decent - as I'm hoping to show here
- speaking it is a bit more of a challenge and I'm not a 100% comfortable with it, certainly when I'm supposed to be having fun and relax. Also keep in mind that I'm stuck on a Euro server and thus voice chat would be a mix of 'English' with cockney, scottish, welsh, irish, french, spanish, german, russian, greek, italian, ... (need I go on?) accents,
IFmy companions are even a bit fluent in spoken English.
So let's keep chat to that chat box, can we? For one, it provides just enough distance for me to feel comfortable with interacting with strangers, and second it forces people to focus on communicating the bare necessities in a concise manner. Spelling and grammar can even be flawed, because people have a chat log and a few moments to decipher it. On voice chat, you have no log and less time.
4) Game pace is crucial factor in being able to communicate with random players passing by. In EQ when you were camping a spot with your group, you could /say to nearby people or /shout to the zone. Good for practical info (/say group full?) or zone banter (/shout Grabbit > Fitz).
Nowadays everyone is an EQ Bard.
5) Instancing: definitely a huge factor in the killing off of MMO communities, but others have already explained it plus I need to go lunch.