In addition, vanilla BM's incense system is quite powerful for self-sacrifice. I don't remember the names of all the things off the top of my head, but there's some brazier-type blocks you can set up near your altar, and if you place some incense items in them, they will consume the incense and give you a buff that will cause your sacrificial knife/orb to glow. Clicking the orb while you're standing near your altar will instantly bring your health down to one heart and put several times he amount of blood in the altar than it would have if you had not used the incense.
For the greatest effect, you'll want to have (at least) one brazier burning each tier of incense available to you, the first being wood ash (if I remember correctly). You will also want as many self-sacrifice runes in your altar as possible, while also making sure that there's enough runes of augmented capacity that you don't overfill the alter and waste the excess blood.