Scrap the languages
I ended up installing three times (Note: scrap any Mail plug-ins before the install, and do an archive and install rather than an upgrade. And back everything up!), and I finally noticed on the third install that there is an option to not install all the languages (I don't know if this was always there on previous installs), but just installing 1 language cut the install time in half (about 15 min) and saved a gig of space.