I think the Expedition rack (or another rack with a large platform) would be especially appropriate if you plan to only use the top of the rack, since it will allow more stability with your cargo. Depending on how you plan to use it, I have been pleased with the hold of a cargo net to hold everything pretty securely. I also like using my Jandd Rack Pack 2, which is expandable, and holds quite a bit.
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Slow Ride Cyclists of NEPA
People do not seem to realize that their opinion of the world is also a confession of character.
- Ralph Waldo Emerson