And still getting better here.
I've reset some Seabios config.h options to defaults and disabled FLOPPY options.
I've gotten all the way to my grub boot, but only on warm booting, and Seabio seems to leave my ethernet controller unstable during normal manufacture bios execution, requiring a complete power off (ie. yank cord) to reset it.
Then I get a call trace in dmesg and then things really slow to a crawl.
Looks like I've got some IRQ routing issues from here.
Attaching a completed log. Cheers!