Trying to be unique
For Vampire to work at all, Blood Magic and healing is required, from my PoV.
Since you’re speaking PvE, healing is really unnecessary. The main goal of vampire build in PvE is the added damage from the life siphons more than the healing + the healing scales bad with healing power anyway. So yes, berserker is a good idea.
While being unique may sound like a good idea, axe really sucks.
For Vampire to work at all, Blood Magic and healing is required, from my PoV.
I would advise against using healing power. The pay off you get from the healing vs the sacrifice in damage or defense isn’t worth it at all. You’ll be getting at most an extra 7 health a hit which is negligible.
I hate to break it to you, but you’re describing a pretty standard Power Necro spec. That shouldn’t dissuade you, though! Vampire necros can be quite strong. For PvE, I’d suggest taking Blood and Spite specializations and going Dagger/Focus or Dagger/Warhorn with Wells for your utilities. The axe… is quite bad.
How to Condi Reaper on a budget
Everything I say is only in reference to PvE and WvW.