All of those are good suggestions for farkles. I would add that the Wunderlich windscreen aluminium bracket is under-engineered and will crack. I even tried taking it to an aluminum welder for re-enforcing welds on the bends, but a crack still found an un-welded bend.
I use the OEM X-Country tank bag. It's a bit pricey, but can carry a ton of stuff with it's expandable top zipper.