Would Bloodmaker Ferrings exist in this category as well? If not, what about someone Compounding Gold?
Brandon Sanderson
Yes, you are correct.
Shagomir
As a Bloodmaker ages, what keeps them from healing the damage and carrying on as a very old, but very healthy person? Do they come to a point where they can't store enough health to stave off the aches, pains, diseases, and other things that come with old age?
This makes sense for traditional Feruchemy as it is end-neutral, so storing health becomes a zero sum game - eventually, you're going to get sick and you're not going to be able to overcome it with your natural healing ability no matter how much you manipulate it with a goldmind.
...Unless you've got a supply of Identity-less goldminds lying around. Would a Bloodmaker with a sufficient source of Identity-less goldminds (or the ability to compound, thus bypassing the end-neutral part of Feruchemy) eventually just die from being too old?
Brandon Sanderson
Basically, yes. They can heal their body to match their spiritual ideal, but some things (like some genetic diseases, and age-related illnesses) are seen as part of the ideal. Depends on several factors.
Stormlight Three Update #5 (Nov. 29, 2016)