I have an idea. but it might be too much to do. I'll post it anyway, just in case.
in the game, by default, there are now 5 types of hearts. red, soul, black, bone, and ethreal
the idea is simple in concept. make each type of heart, mainly red, gray, and black into their own counter, perhaps if possible, a Gauge, 3 icons of the 3 colored hearts to display the number for each heart. for ethreal hearts, a white outline forms around the red heart to show you collected one, as collecting a second makes a new heart, and more health. for Bone hearts. I am not too sure. though adding a Rip, a single rib per bone heart on the red heart. each rib can be hollow to show it empty, and fill with red to act like a filled bone heart, like mini gauges that hold 10 hp each.

just an idea. you need not try it if you can't program it to do that