So whether it be broken/missing libs or bad USB device enumeration causing upowerd to be either not available or slow to start, it would seem unity-settings-daemon could at least be improved to be robust enough not to segfault if upowerd is not present.
In the meantime, I was able to solve the USB device problem to work around upower.service slow start by adding the kernel commandline parameters 'usbcore.use_both_schemes=y usbcore.old_scheme_first=y'.
So whether it be broken/missing libs or bad USB device enumeration causing upowerd to be either not available or slow to start, it would seem unity-settings- daemon could at least be improved to be robust enough not to segfault if upowerd is not present.
In the meantime, I was able to solve the USB device problem to work around upower.service slow start by adding the kernel commandline parameters 'usbcore. use_both_ schemes= y usbcore. old_scheme_ first=y' .