Double Checking - Self Critiques

I spent yesterday painting on one of the PPP (People Painting People) portraits.  I chose the one that was bothering me the most.  This part of the process takes way more time than the actual painting done from life.  Maybe because this one needed a lot of help.  First I determined that my drawing was off a lot proportion-wise.  So along with moving the eyes down about an inch and also the ear that was the only part of the painting that I originally liked, I tried to change her expression to a more pleasant one.  I struggled with the lighting.  First I had too much light and so the overall painting was coming out too dark-thus another coat of paint.  I should have cleaned my palette and didn't so I had some muddy color to contend with.  I repositioned my back mirror last thing last night and saw some other problems to correct.  This morning I reappraised the situation and took photos.  It's always a surprise how instantly the mistakes pop out on a photo.  OK, so I made a list of corrections to be done and will wait until later (maybe today) after I've warmed up, to make those.
Yesterday I received Carol Marine's new book in the mail and read about 1/3 of it last night.  She has some mighty good tricks up her sleeve.

There is a big difference between a sketch and a formal portrait, and also between a sketch done on location in a couple of hours and a touched up version.  I much prefer the original, usually, but sometimes other work must be done to make serious corrections. I try to remember to take a few photos to document the original light and, even when in doors with controlled lighting, the light will change because of outdoor conditions---I know, hard to believe.  So I take a few as I go along and the model relaxes and things change a little.  It's nice, sometimes, to be able to have those reference photos to 'improve' the design a little.