I appreciate you following up on this.
I wish I had more details to share with you, but at this time, we're still collecting feedback on this feature request. If we have any updates on this in the future, we'll post these on our changelog and on our Updates blog, so I recommend keeping an eye out there.
I would really like to see something like this too. I have hundreds of individual shipping rates across dozens of countries and weight bands, and manually uploading these rates would take ages. Not to mention the room for human error.
There must be a way to import and export shipping rates via CSV.
So we started work on an app that will allow you to edit your delivery profiles with a CSV/spreadsheet style interface. We're working on importing/creating new rates as the next feature. If anyone is interested in trying out as a beta tester, ping us at firstname.lastname@example.org. Thanks!