Thanks for the help everyone. The TP-Link WD-9970 v2 router is definitely to blame.
I switched to the Plusnet router, and when I max out the upload I can still browse and YouTube works if you don't go too crazy with the resolution. My pings have also dropped from 1200ms+ to ~18ms. This is all being done over the Ubiquiti AP AC Lite access point.
You couldn't be on a work conference call or use the Apple TV whilst uploading, but at least the connection is usable now.
I switched to the Plusnet router, and when I max out the upload I can still browse and YouTube works if you don't go too crazy with the resolution. My pings have also dropped from 1200ms+ to ~18ms. This is all being done over the Ubiquiti AP AC Lite access point.
You couldn't be on a work conference call or use the Apple TV whilst uploading, but at least the connection is usable now.