[Executor]

Caelum can be a bit hard to handle, esspecially in MA, but I think they're a good choice. At the very least you will have excellent mobility which is great for raiding.
As for blood magic, I'd advice against it. You'd sacrafice a lot to get a stable or any kind of blood economy going. Your pretender would be tied up from the start, and it would be a very slow and painfull start with no much to gain. You'd forsake design point, pretender hours which could be put to better use, research detour which I advise against with Caelum and you wouldn't have much to compensate for it all.