There is a workaround, as I discovered. Download two updates before starting the installation process, KB3083710 and KB3102810, and copy them to a USB flash drive. Install Windows 7 with SP1 and leave the network cable disconnected. Install those two updates from the flash drive before connecting to the network and running Windows Update for the first time, and you can cut that horrendous delay down to a matter of a few minutes.
Even then you have many hours of work ahead of you. When I started over, using that workaround, it still took nearly three and a half hours from the time I started the clean install until those 216 important updates were finished downloading and installing.
And then, after rebooting and checking Windows Update again, there were three more updates. And 26 more after the next restart, and two more after the next restart...
In all, I spent about eight hours to finish installing Windows 7 and something like 300 Important and Optional updates (I lost count, honestly). And each restart along the way demanded my manual intervention.