I beat the first area, and the game is actually pretty fun. I haven't had a chance to mess around with PvP yet, but it seems like a fun planetside-esque constant open fight for territory.
At the beginning, if not throughout the game, missions will be basically "talk to this person at the end of this area" to get through each section of an area you need to defeat a certain number of monsters or meet other requirements, and experience is rewarded by clearing areas or doing side quests that you can find in each area.
Melee attacks are a bit of a bitch since side stepping and jumping takes forever, so you need to rely on normal movement to avoid attacks which is a almost impossible, but ranged attacks are pretty easy to use, and kind of completely OP in PvE if not PvP. You'll learn timing after your first two or three monster kills and I haven't been hit by an attack since.
Finally, since there's a giant territory war, I assume we can only play together if we're all allied to the same country. I don't know about Envy, but my main is a part of Gevrandia. It seems like you can have multiple characters in multiple countries, though.