I am very opinionated on Blood Magic marriage pieces in that I believe they should pull blood mages to the community rather than turbocharge any who happen to be in it. I think this is a good change instead of liturgies offering blood magic multipliers.
The issue isn't "only useable" or "only can be lead by" if one has both magics, that's actually fine. The issue is that blood rituals fail. And it's really dangerous. So you're rewarded for having blood mage friends who can raise your modifier. This prevents 2 - 3 people from running really high power event rituals alone, generally. The problem is that an outrageously high blood magic modifier could be obtained by just a few people who have happened to kill several others, and then they can privately perform this entire spell list. That's pretty strong, no matter what the spells are.
Normal blood magic rituals adjust at 12, 13, sometimes 15 out of 20. You have already reduced the chance of failure to less than a coinflip once we account for blood modifiers with liturgies and soul fragments on a lot of these spells. Failure is an important part of blood magic marriage pieces, and this one has lost that balancing element by adding liturgy bonuses. I am not sure if I am reading this right too, but it seems like many of these spells are also just outright given to ... single mages? As long as they know both? I don't think you should do that. Blood Magic is about group rituals. You should up the count of people needed to perform these spells. If this isn't about Group Rituals, it's more or less just a free Feat for Blood Magic/Mystics.
Blood magic formatting normally goes (Requires 3 Blood Mages, one of which must be Tier 4). Only the blood bending spells allow for single person use.
I like this piece, I have a few more issues if you'd care to hear, but these are my surface thoughts. I am of the opinion that marriage pieces should promote direct reason to roleplay between both groups, and not provide power to one side of the equation more than the other. I like the Naz marriage piece because haunted houses are evocative, symbols in the sky are cool, and cursed calling cards are a devil staple. But it collapsed the risk of rolling & I dislike that.
Just my two cents, though.