The Denon AVRX1800H showed up. Swapped the speakers, Fire Stick 4K, HDMI-adapted Wii, and TV over to it.
First thing I found is that having configured it for bi-wired front speakers, the front L/R test tones were inaudible until I swapped which outputs each front speaker's drivers were connected to - does this mean one set of drivers is dead on my tower speakers? Hopefully it won't matter since I have bookshelf replacements on the way (provided they are in good condition).