Don't be, I'm probably where you are at now too, and your reflections on shooting are very useful. It's interesting I also use the exact same focus peaking setting as you do (yellow, medium)I'm also embarrassed to post this particular post, as I don't see how any of my observations could help anyone here but maybe there is someone here as green as me.
I too use Mid Yellow in daylight, but switch to mid white at night indoors, because my living room is very dimly lit, so there is very little contrast for the Peaking to pick up. I need to be able to see the slightest little speck of shimmer, and white works pretty well for that.
Edit: Oh yes, and I personally like your third post best in terms of pose. The woman has a very natural but expressive look on her face, rather than the more posed shots of the other two. I'm not sure I'd have cropped her head at that point though. I'd have probably gone portrait orientation and moved closer.
Don't be embarrassed, I for one, enjoyed your shots very much. I feel I can learn from anyone no matter their experience level. So, thanks for sharing.
I haven't experienced with anything but Mid, but I'm finding it pretty balanced and useful so don't feel the need to try Low or High. However, I do find different uses for Yellow and White, I personally don't like Red, I find it too overwhelming (maybe it'd be interesting on Low ?).