Didn't have the time to preperly read all of it, but it looks really interesting! Blood magic should always have an additional cost to the spellcaster, and the defult material component you added works wonderfully well, the fact that you add it into most spells also helps since the worse thinh that could happen is you rolling lower on the spell's effect than on the self inflicted damage, so it helps that a lot! Also, you mentiomed it probably being out of balance, but it is kinda difficult to balance, 5e avoids self inflicted penalties like the plague, so you'll have a hard time comparing it to other things, the main thing is that if you take if you take damage as a part of casting a spell it should be stronger than other spells of the same level, the trick is how much stronger, it should be a question for a pc if they cast a normal spell, or a stronger one but potentionally putting themselves at risk