Voodoo is a strange upgrade (although interesting mechanically, its theme is somewhere out the window in a field of dirt).
I do like the idea of two angels, one with the shield and the other with the sword. Very nice idea there.
Although if you really really want this to be a counterpart to Seraph, you could raise HP to be higher than attack (and obviously lower attack ^^) so that it slowly brings itself to Seraph's levels (but definitely should be able to get better stats than Seraph using at around two or three uses of its ability on itself, unupped at least), yet lacks the shield, while Seraph has the protection, but not the chance to deal as much damage without a sword.