Hi, @craig ,
I also have an update. I turned of development mode on Z1, which has no heat sinks at all(how did ‘net’ get here before?). I switched wifi to 5ghz and was able to achieve 1 hour streaming time via WiFi. I was checking some articles about heating/power consumption of wireless chips on some android devices, so I realized that using 5ghz instead of 2.4 may help. And it did. I think there is also some space to lower cpu power a bit, bandwidth usage, etc. Quality decrease would not be noticeable, but will have to do more tests. Heating is of course still an issue, is there a way by Ricoh, to increase sensitivity of heat sensor by 5%? I mean to turn off device a bit later, when it’s a bit warmer. I know that they do not want to burn the device, but I’m not sure it will burn… anyway they could know if it does? 
Regarding seeing logs during development, I was able to turn back on logs by adb command, I will add here later.
To enable logging again on latesf firmwares, playing with this worked:
adb shell setprop persist.log.tag 0
Im not 100% sure about the proper value, it may be 1, or --Log.
Laszlo