Hey Rev, I think I know what you need, Icon's Urban Tank Bag. I saw one at the local dealer and it is probably the most versatile tank bag I have seen. It has four small magnets that are very powerful but weigh almost nothing. It has a big grab handle to carry it with and it converts to a back pack with wide comfy straps. It has tons of pockets and grommets to run your headphone cords through. It has a soft bottom so it won't scratch your paint and you can flip that part down and strap your helmet in it. Check it out
here.