I personally wouldn’t consider Diablo 3 necromancer an upgrade over the Diablo 2 version; as once again you have no army to call upon. Sure the Diablo 3 necromancer has some builds that makes it popular and powerful in some aspects. But since it doesn’t fulfill the fantasy of having an army of minions, I find it a downgrade compared to it’s predecessor. But that’s only because the diablo 3 developers had a different vision for the Necromancer than what some of us may had hoped for, and as you can see, it had nothing to do with pvp.
Also considering that there was almost no way to protect yourself from magic damage in Diablo 2, and there was no raw damage reduction stat as there is in Diablo 3. A Diablo 2 Bone Necromancer (with enough fcr, mana potions, and an enigma) can certainly mow players down instantly in a flurry of Bone Teeth, Spears, and Spirits.
Where had the developers say that players will need to pvp in order to progress, level up, gain items, unlock contents and/or other features? In short will players need to kill one another in order to get through and beat the game? Unless the developers had said anything of the sort, then Diablo 4 is by no means a pvp game.
Take a look at the gameplay trailer and notice how the Sorceress couldn’t freeze the barbarian, when in earlier segments she was able to freeze monsters in the same number of hits or less.
Scripted or not, it shows that skills with cc effects may affect players differently from how they affect monsters, or at least that could be the developers intent otherwise the sorceress would’ve just froze the barbarian.
And the rest of their interview as well as blogs that came after blizzcon had done nothing but emphasize pve aspects, so again, the game is mostly pve with a little pvp thrown in.
Those games were made primarily for pvp, unlike Diablo 4 which will be made primarily for pve.
Well not much to be said, since you’re under the notion that Diablo 4 will be a pvp game (despite the developers saying nothing of the sort). I for one hope that they continue developing the game with pve foremost in mind, then followed by pvp.