Turkmenistan, Uzbekistan, Kazakhstan...any pointers???
Do a search. I have described what I did through Uzbekistan, Tajikistan, and Kyrgyzstan. Happy to answer any specific questions you may have
Thank you. I found your post from 3 years ago
Impressive that you took your children.
In case you haven't encountered it yet, the MIR company specializes in tours to that general area.
Our pals at Lyuba Tours (who are key to Rick Steves Bulgaria tour) also operate a small selection of tour dates in your area of interest. See https://lyuba.tours/we-explore/. I had an awesome time with them on a Kyrgyzstan (+Kazakhstan) tour two years ago. (It was co-operated with SRM Tours, our contacts in Turkey, but I don't see that they have any departures currently scheduled.)
As of about a year ago, Uzbekistan made it much easier for Americans to get a tourist visa, so tour options there are probably increasing.