I'm not able to comment on the bokeh of the RF 35mm, but I can say that the 35mm angle of view is not a "portrait" lens view by any stretch, except perhaps for a near full-body shot or one where some slight apparent perspective "distortion" is acceptable to otherwise get an otherwise excellent picture. To do a natural looking head and shoulder to very tight head shot, at least a 50 mm or, preferably, an 85mm to 180mm focal range will yield the best results. Too short a lens renders the front of the face too big in comparison to the rear most portions, and too long a lens renders those rear portions (ears) too big in comparison to the front of the face (nose). The happy medium for these shots that look most "normal" to the human brain happen when the focal length increases as the overall size of the face in the image area increases. I've been doing this for a living for 40 years, and i can tell you this is true. Yes, you can get a fantastic portrait with a 35mm lens, but it is harder to do and to artfully avoid the perspective from detracting from the positive overall look of the image. Finally, 35mm is the widest lens I'd ever use to shoot any "portrait of a person, if the person is all that you want to consider as the subject of the image. For environmental portraits, where you want to include many things around the person, in order to make some point about that person, then all such rules about focal length are null and void, and very wide angles often work best.
So, what to do? Well, here's one thought for you. I'd go with one of the EF to RF adapters, and shoot an inexpensive lens like the "nifty 50" or the inexpensive 85mm f/1.8 instead. But, of course, YMMV, especially if you don't currently own either one of those, or you'd rather not invest in any other EF lenses, new or used, right now.