How interesting that you did this test, because two days ago I made some test exposures to do exactly what you've done. My exposures were of plants in full shade, so even lighting of low contrast. I plan to use a dilute developer and let the film develop for several hours. Regarding your exposures, it is evident that progressively each exposure is lighter than the previous. I can see that any of the three would be appropriate if that's your vision of the final image -- and clearly having that vision is part of the Mortensen process. This is something I'm trying to get more into my head: when I consider what to photograph, I am often paying most attention to the subject (obviously) and how the image appears on the screen or in the rangefinder, but I'm not paying enough attention to the contrast within the image and how I should best expose to maintain the tone relationships I want. A true learning curve...