In addition to color problems, the two figures are too similar in shape and they are too similar in size, so the painting is not interesting. It was an experiment, so what the heck, I decided to scrape off the woman's head and start over:
Maybe I improved it a bit:
And to report the results of prior experiments -- the masking tape that I used to tape the oil paper to the board came off fine after the paint dried to the touch. Freezing the left over paint, as recommended by Bernard Fallon, worked just fine, too. After defrosting, the paint was like new. Some experiments work!