Honda’s rear carrier, available in the US, has been discussed in several threads. Some like the look, so not so much.
Personally I think Honda did a pretty good job of adding some “function” without distracting from the “form”.
My wife loves to ride but feels more comfortable on a bike with a backrest. That’s one accessory I haven’t seen offered yet. I ran the idea of a Givi top case with backrest pad by her, but my wife wasn’t thrilled with the look.
Under the theory that “something” often beats “nothing”, we purchased a Nelson Rigg CTB-250 roll bag and secured it to the rack. The bag has an insert to keep its shape, and filled with raingear and a small backpack the roll bag is quite solid. It’s fairly unobtrusive at 15” long and 9” in diameter.
Back to the rear carrier. It was on back order 2 weeks but was worth the wait. I saved $54 buying it when the local dealer had a 20% off accessories sale. It was a fairly simple 30 minute install requiring one 6mm hex wrench, and after it was on I figured out how to install it in about half the time. Here are a couple of close-up pictures.
Getting ready to try it out in a few minutes!
Edit: back from a short 35 mile run - the wife said the "backrest" was just "ok". It has about an inch of give and was a bit hot, but better than nothing, and with a bonus of bringing a couple of small items back from the store. But we do need to get a proper backrest sooner or later.