The only Orbi I've used is the tri-band RBK50 2-pack. The hardware is good, but there's one annoying thing: you can't manually set the channel bandwidth to to 2

The only Orbi I've used is the tri-band RBK50 2-pack. The hardware is good, but there's one annoying thing: you can't manually set the channel bandwidth to to 20MHz. This would improve signal strength and range, at the expense of bandwidth. The 'coexist' setting is meant to switch to 20MHz when needed but, from what I've read, the setting isn't very effective. If I lived in a place with a lot of wifi APs, I'd do what you did (string cables) or else use an Asus mesh wifi setup, which allows more fine-grained control of wifi settings.