I read over your threads and when you started talking about soft sides I thought I would add my two cents worth. Personally I played with the idea of what would be best: hard cases or softsided bags. I agree with klr4evr about if you have soft side bags you should have racks.
But that is where I made a big change from the two options. I found the Wolfman Boulder Beta Rear Bag. What a great choice. It straddles the seat where a passenger would ride giving me a bit of a back rest. The interior features include 3 dry bags and exterior is as tough as my KLR. Now for the two best points!
1. The bag mounts solid to the bike with 4 straps. Quick on, quick off. So great for after riding, you can in minutes remove all your gear from the bike and take it into your tent or motel room.
2. The tunnel bag has 60 liters of capacity...the same as a full sized backpack! I stuff in my camping gear, clothes and food in it without problem and still straddles the seat, but doesn't hang down low on the sides. Instead, it only hangs just a bit. No side racks are needed!
I love this bag. Take a look at it!