3. It's spotty, NA cluster's main populated servers are Gilgamesh, Balmung and Lamia, everything else has various levels. So you'd do well to research.
I'd recommend NOT joining those servers. They're too populated, and they tend to experience more congestion and problems.
I'm on Hyperion, which has a very healthy population without being overpopulated. If you find a site that guestimates population figures, then I'd recommend joining a server that's roughly Hyperion's size. You won't be disappointed.
2. In a vertical progression game like this, yeah, End-game is the only thing left.
Keep in mind that most of the level 60 content -- even the newest stuff -- isn't "endgame" in the traditional sense. Outside of a single eight-man "savage mode" raid, there is really no content in this game where people form statics/linkshells/etc. to grind for rewards on a regular basis. You'll queue up and be matched with strangers for most of the level 60 content -- you simply don't need established groups to do most of it.
In my opinion, what it comes down to is this:
If you're a hardcore-style player who tends to play for several hours at a time -- and if you want a game that you really want to have to be able to pour time into in order to be successful -- then you're probably not going to like FFXIV. You'll either be irritated by gear being "obsoleted," or you'll run out of things to do.
If you've become more casual in how you play video games -- or if you simply don't have the time to be hardcore about gaming -- then you may appreciate FFXIV's more casual approach. It's easy to hit the cap, and it's easy to get caught up again if you take a break. And if you can play just a little bit a few times per week, then it's pretty easy to stay caught up, too.
But I'm sure you can see how that approach swings both ways for different types of gamers. Edited, Mar 23rd 2016 2:49pm by Thayos