I am by no means someone who has played on privates a lot. I was on both realms on Nostalrius and I will put my critics here and I hope the developers can listen and do something about it before players begin with raids. Nostalrius provided a Vanilla experience to some extend, indeed. But the end-game bosses was by far not as difficult as they used to be.
I suggest you improve their spells, and/or make them hit harder/altering their health. I am no developer, but I am a fan of challenges and I think users who decide to play "Blizzlike" on private expect the same. Now there is already a lot servers providing what they claim a "Vanilla" experience. That isn't true, I can speak only for Nostalrius which I personally believe had the best management and by far the best Vanilla experience, except the raid content.
If the developers behind valkyrie can do something about what is mentioned above I believe more experienced users who want that same "challenge" will come. Because if you look at the expansions released after Burning Crusade, there is no challenge anymore, they simply decided to make their content easier in hope to gain more players.
Take it into consideration, because providing same or similar difficulty as other realms isn't going to make you any different.
I'd also suggest you to open Zul'Gurub before Molten Core, on Nostalrius you could be twenty players in a 40-man dungeon and still take down several bosses, how is that competitive and I don't understand how users find that enjoyable.
Cheers
