What if Isaac's heart Still made enemies target isaac instead of the heart? It is really difficult to use that item... at ANY level of play

That would defeat the challenge of using the item. However, the added chance to collect bonus hearts from enemies should keep things fair until the womb.

The updated Yum Heart seems much to powerful. Perhaps changing it to a floor based setup might be better? For example, until Womb/Utero you gain red hearts. In Womb/Utero you gain soul hearts. And then any stage beyond that is black hearts (Cathedral, Sheol, etc.). Keep in mind balance with both Normal and Tainted Magdalene however.

This mod is not compatible nor updated for repentance. The modding API is broken, and I cannot update either of my mods at the time.

Yes I realise that. This is a suggestion for when that does become possible... I don't know whether or not you do already have balancing plans (and I'm sure you do), but this is simply my view on it for when (as you have said yourself) you will update it for Repentance once that is possible. I'm currently just playing AB+ until modding does become an option.

However, I actually think a better idea might be to have the yum heart change to soul heart generation only once you have no red hearts at all (except bone hearts). And then you can gain black hearts once your maxed out on different types of hearts. And then the lives if you wish to keep that mechanic.

It really is just a suggestion, I am aware of modding issues atm.

With the next update, I'll definitely need to nerf my version of yum heart. Health generation as a whole has been nerfed by Edmund, and several items are now too strong in this modpack.

Makes sense thx for the info :)