My impressions;
The Portrait category looks thin compared to the others, that is, for Travel and Human Figure you have sub-categories, but not for the Portraits. After looking at the others I kind of expect more choices in Portraits. That said, I'm not sure it makes sense to "invent" a sub-category to make it consistent, so I am conflicted.
Compared to the others, there are a lot of pieces in the Portrait section. What if you removed "Charles, Column Capitol" and "Charles, in Henry's Garden"? At least on my monitor, the color on Column Capital is a little off, and Henry's Garden is a little weak compared to the others (IMHO).
That would bring the number of images there a little closer to the other sections.
As for mixing the color and B&W, I'm fine with that, and I think the transition into the color works well with "Dorothy Kloss". The transition back out is a little jarring to my eyes, but I think it's handled well because of the dynamics of the sitters' facing each other and the setting change.
I like the work.