There's no big need to take action given the dimensions you have described, and the size of the baby plants. Best to leave them alone if they look like they're growing, then when they have a reasonable rosette and a good set of roots they will be much less sensitive to transplant. That plant will be good in a 4 inch pot for life, or at least that's my plan for the two purpusorums here.
I start small leaves in my usual minimum size pot (4 inches) or grouped together in a 5 inch pot maybe, filled to about 2 inches. They obviously are not using all that real estate for a few months, but that size pot takes longer to dry out, and I'm not a fan of extra watering if I can avoid it.
