Bood mages don't seem to me like
If you know some blood mages, please tell them to email Riot for input on Vladimir's character design.
Maybe have them stress contracts with Lucifer and goat sacrifice while you're at it.
As far as Vlad's kit goes, it does't have much to do with blood at all. Change the visuals slightly and it would still work. Hell, until the rework Mord's Q was basically the same animation as Vlad's E.
As a character the only thing they need to keep is a ranged ability to heal, other than that they don't really have much of a base for his design anyway. They can't even come up with skins, seeing as 3 of them are vampire when they stress that he isn't a vampire.