I played from launch, for the first month that came free. It has the potential to be an excellent game, but after I got to level 40 things started to feel a bit flat. Its not surprising, to a degree, that content wasnt fully available across all the levels at launch, but given the speed of levelling one would have hoped they could have predicted this content gap after Beta.
You can get into a pvp game via the 'community' window, there is a tab in there for pvp matchmaking. You choose the style you want to play (capture the skull, team annihalation etc) then wait to be matched into a game. I dont think its server specific, it should be available on all, but it will depend on the number of other players searching so you may have more luck on a pvp ruleset server.
I played on a pve server and only ever got into one game, despite trying many times.
If the deves live up to their promises to include more zones & content for mid levels, and get the guild cities working / siege warfare as promised I will probably go back to it, but not until then.
The day / night time play styles only go on until you are out of Tortage, I think the idea is to give a feel of your own personal story and let you learn the game solo. I thought it was a neat touch.