It's not a big deal to have some stem showing, but the rosettes getting smaller might mean the plants are not well rooted (could be related to the varied history you have described) or they're not getting enough water. That would be my guess. The four rosettes look like they still have plenty of life force. Once you find the right rhythm they should be just fine.
Unglazed clay pots can dry out quite fast if they're in the sun, or in a low humidity situation. For that reason I avoid them in favor of regular plastic pots for plants I don't know that well. You can place the clay pot inside a slightly larger plastic or ceramic one and reduce the effect. The difference relates to the way clay pots dry out through the sides and not just from the top. I know from trial and error that some plants (eg. Aeoniums) are not at all pleased with the clay pot lifestyle, at least when grown on the dry side, as is my custom.
So I have learned to be careful who I put in a pot like that.
