I'm note sure about the female tanker. Her proportions don't look right (especially next to the male, who I realise is slightly 'heroic'). Granted, you want her to be slighter than the male, and you don't want to over-emphasize her female features and end up sexualising her as a figure. But she's ended up looking a bit weird - more like a young male than a woman. If you're going to do a female tanker, then she might as well be recognisably female. I'd suggest narrower shoulders, a bigger head and perhaps a bit more shape. There are other female tankers who were more curvy - maybe they'd be easier subjects? Maybe leave the helmet off as well?
