Blocking is just a new gimmick. What is the fundamental difference that separates this game from mainstream MMORPGs?
Equipment loss upon death? This not only drives PvP, but creates a constant demand for player-made equipment.
Player-owned, conquerable structures? Ebon mines, sawmills, housing, etc. Defending moons in Eve is one of my fondest MMORPG memories.
Player-created content? Forts, ships, weapons, wars. I don't want to be stuck on a map and told that nothing I can do will ever change it. The game, is it were announced, can never have something like http://www.rockpapershotgun.com/2008/09/09/the-great-war/. They've already told us that player interaction is faction-based, so an arbitrary choice at the beginning of the game already picks our enemies for us, rather than friendship and enmity forming through player interaction. The faction idea just needs to die already. Telling us that this nameless, faceless guy you can't talk to is our enemy simply because he picked a different race when he created his character is stupid.
There are no bad guys in faction-based pvp. Only people who picked the other team. I want to be able to decide to be good or bad. To come up on a guy under attack and have the option to help him or help kill him and take his stuff. To be a highwayman or a lawman. To join a guild to help them in a war, or to feed information to their enemies and swipe things from their bank. Picking your enemies, deciding to be good or bad, making a name for yourself through various professions: this is what makes a sandbox.
Without things like these, I won't play it, for the same reason I won't play Warcraft, or Rift, or EQ2, or LOTRO, or Aeon, or Warhammer, Age of Conan or any of the endless slough of theme park MMOs. A sandbox MMO is the only thing fitting of the Elder Scrolls name.