I'm glad you like the portraits, they definitely turned out better than I hoped! It's really emboldened me to try my hand at naked full body images that show the gain pattern, weight stages, cellulite, stretch marks etc.
The barely mobile reference for mobility scooters is that they should appear as an option that allows you to go into town when your character feels too weighed down by their size to make the trip. I'll look at usage for the girls, as it would make sense for them to use them at that weight stage as a matter of course.