You want to kill that beauty with a rack? Why not a backpack or a cycle pack, I got a sweet Brooks cycle backpack, Holds alot of stuff. Before that I had a brown leather rucksack I used for years with my mopeds, a $4.00 yardsale score.
Some are expandable if you want to go crazy. I have camped out of these small packs using ultralight camping gear, hauled 12 packs, all kinds of stuff. Great if you need to ditch your riding jacket when the temos start climbing.