Hi Cornelius,
I noted my answers between your questions:
We don't plan to take a guide, we are experienced backpackers but the remoteness of the region warrants good preparation.
We are planning on taking a satphone for emergencies. I read your other post about the signal being traced. Thank you for that info as well.
Answer: google around. Penalties can be very severe if caught. Consider a Delorme Inreach if you want to remain connected
Our biggest concern is our 10 year old. She is fit and is used to walking in the Swiss alps above 1500m, that said we are planning to acclimatize for a week before starting any longer walks.
How many km a day were you walking during your time there? We usually walk a third of our daily km when our daughter is along so she manages 10-12km a day and still enjoy it. We thought about doing 2x2hr/day and seeing how far we get.
Answer: with that schedule in mind, the Zanskar trip might be too risky with a child (250k, although 40k or so can be hitched). You do your own research: wikiloc contains some Zankar trek gps-files. Download one as a kmz-file and open it in Google Earth. If you play around with Google Earth, it is possible to get a chart with the length & altitude of the trek.
Also, did you get the two guidebooks I recommended? Might help with your assessment.
At the end, I will be up to you and your family to make a final decision.
Might the Zanskar trek be a good idea? Having the option to hitch a ride might be nice.
We are thinking about preparing our own freeze dried food to take along, or can we find light trekking food there?
Answer: as said in my previous answer, I think Zanskar is a bit risky with a child. Also keep in mind the long & bumpy rides to & from the trailhead of that trek. That might be an (extra) killer for a child.
I would strongly suggest the Markha trek with a child. Can be extend in the west by starting from Lamayuru, and in the east with the Kharnak trek. The latter will be remote, so experience with backpacking is paramount.
We usually use a catcan stove? Were you able to find alcohol there, which kind and what brand and where? Or did you use gas?
Answer: I use an MSR wisperlite, so I just fuel up unleaded petrol at a petrol station. I am uncertain whether the supply of gas cartridges of alchohol is available & reliable in Leh. Can’t help you with that. Maybe google might provide an answer. Also, the thorntree of Lonely Planet is being monitored by some experienced Ladakh trekkers.
We use a sawyer filter for water, did you find enough running water? Is the sawyer filter enough?
Answer: I just use iodin tablets. Can’t compare it with a sawyer filter as I have no experience or know how about it. But water is generally clean.
Was it a problem to do wild camping? We prefer to sleep outside rather than homestay. Did you ever experience problems camping outside, police, military, drunk locals ( we've had all that happen which is why we ask )? Did you prefer to camp near villages or away from people?
Answer: camping is the norm, so no problem. But it often comes with a very small charge. Never saw a police officer in Ladakh. No armed military in the mountains (only army engineers where roads are being built). But you might pass some check points on route to/from the trailheads Never encountered drunk people. But sometimes felt a bit uncomfortable when walking past camps of road builders (where I sometimes spotted alcohol consumption, not problematic though).
In general, people are very friendly.
What did you use for bathroom breaks, did you bring paper, or is there materials to collect you can use? I guess leaves aren't in abundance.
Answer: mostly wilderness toilet (I pack out my own toilet paper). Sometimes the local toilet when available.