I don't think I'd go for anything that's digital and old. Not because of IQ so much, but because of the nature of digital cameras and spares etc. For portraits, I would have loved to have been able to stay with Hassy 500 Series cameras, but film is so expensive and servicing shuttered lenses may be problematic - I am not sure about that, but if the companies have closed shop, what are you gonna do?
I have never found the 24 x 36 format good for portraits; too tall and, consesquently, too narrow to allow much space you may want to use; not all portraits get shot against white Colorama that, yes, allows you easily to clone width to your heart's content.
Looking back on my life, I wish I had sold neither any Nikkor lenses nor my 'blads. I also wish I'd kept my Bronica 6x7 (GS-1) with the single lens that worked nicely -for me: the 250mm. I have a poster on the office wall shot during the 80s with that combo; it still looks great and the detail is amazing.
The problem was always what you face: trying to squeeze different types of work out of one system. I resolved that, more or less, by having two systems: 120 and 135 formats.
Rob