Re: Several points
"1) I would think a rat with a drinking problem would be more in need of a liver than a kidney."
True. Although I'm not sure if rats, like humans only have 1 liver & 2 kidneys.
"2) This still requires you to have a kidney to provide the scaffolding. Thus, it won't stop the need for donors - only reduce the need for recipients to be on immunosuppressant drugs."
Actually it will. The original kidney template could be provided by the patient (after all the bulk of its function is not working) alternatively any old roughly matching sized kidney can do the job, including one from a recently deceased.
"3) If we could figure out how to print the needed scaffolding, rather than needing an organ, THEN this would be great, unless...."
Some versions of this already exist. You may remember a rat with an ear on it's back. The fact it just needs a roughly (not necessarily living) template opens up the field a lot.
"4) Since this uses the patient's own cells, if the reason their organs are failing is a genetic issue, they will be getting an organ with the same failure, unless we can work out how to treat the cells beforehand to remove the genetic flaw.""
Not necessarily.
AFAIK this work use embryo stem cells, so the default source is nothing to do with the donor of the cells. However at least some organs seem to be growable from so-called "precursor" cells (heart cells are an example) which appear to be a half way house between stem and fully differentiated cell types.