Modern HB bags won't work for bikepacking situations because the shocks and vibration will cause the mounting system to rotate downward or break. Plus they don't hold sleeping bags or tents.
Here's a pic of the drybag only idea. It holds my one man tent and poles.
The buckles of the double ender snap over the flats of the drop bars. They do make a bump but you can refold the drybag ends to get them to lie where you want. The yellow thing is my sleeping mat which tucked in the aeros nice but does look odd. I have since put it somewhere else. The pics don't show the red retaining strap but it is just a piece of webbing that acts as a safety in case the buckles of the drybag holder open. Turned out the whole holder itself was redundant.
One thing I like about the Revelate sweetroll is the egress pocket you can add. Those systems are nice enough but pricey for what they do.
This one held my two man tent with the poles along the top tube.
