... Except for heavily splashed melee-pale masters.
But for casters, no. At level 12, I'd much rather be using wraith form, if for nothing else but the run speed. I don't need enchantment DC, because everything in two fireballs or less. Maybe the enchantment DC is useful at level 17 when I start running vale, but one level later I get lich form, which is pretty much flat out better.
Really, the only time that I would want to use vampire form is when I don't want the permanent featherfall of wraith form.
Suggestions:
-increase run speed of vampire form - making it on par with wraith form
or
-Provide a ~10-20 concentration bonus in vampire form. This would at least give it a decent advantage in group settings (when concentration starts to matter due to dungeon scaling).