having worked in hospitals and in dialysis, here is my advice (for what it's worth, and you may not agree).
I think either job is too challenging for a fairly new grad (you don't say how much experience you have, and in what area of nursing). Why? Either way, as an acute apheresis nurse covering 74 (!) hospitals (my goodness, you would probably have to do a brief orientation at all 74 of them! I had to do this at the hospital where I did acutes for a short time while working in a chronic dialysis clinic...) or as a home dialysis nurse, you will be on your own much of the time. Yes, there will be other RNs in the hospitals, of course, and if the pt crashes you can call a code. However, they will most likely not be able to help you with anything related to the apheresis procedure, machine, pt response, interventions, etc. Your orientation could not possibly be long enough - unless they have you train with an experienced nurse for an extended period of time (unlikely) - to cover all possibilities. And as a recent grad, your clinical experience in general is still very limited.
As for the home dialysis position, much of the same applies. Again, you will be on your own, and there won't even be other nurses around if something happens to the pt. It depends on the training, but in my experience it takes at least 1-2 years in a dialysis clinic setting to learn all you need to know to be able to function independently (and most advise new grads not to go into such a specialty right out of school).
I encourage you to pursue dialysis or apheresis (both are equally technical and cutting-edge, IMHO), but start out in a setting where you will be with more experienced nurses for at least a year before you strike out on your own (e.g., dialysis clinic, blood bank).
. Good luck to you, whatever you decide to do!