If you already have the barbag you can get the seatpost mount if you'd rather have it behind you.
You'll need these two parts (I'm told the Ortlieb fits the Klick Fix, but haven't tried it.)
https://www.sjscycles.co.uk/luggage/rixen-kaul-seat-post-extender-for-klickfix-adapters/
https://www.sjscycles.co.uk/luggage/klick-fix-cordo-cc100-qr-handlebar-mount/
Yes, the Ortlieb bar bag fits on the Rixen-Kaul Klick Fix mount. That's what I use.
Anto, I had the same problem on my Nomad, with the bar bag interfering with the headlights. What I did was lower the bar bag by mounting it on a Thorn t-bar and mounting the headlights above the handlebar on an accessory mount. This only works if there is enough space between the bottom of the bag and the front tire so that you can lower the bag.
Here are the Thorn t-bars:
https://www.sjscycles.co.uk/search/?term=thorn%20t-barThere are two sizes: 55mm and 105mm, which is the distance from the mount to the bar. The longer the distance, the more your steering is likely to be affected by the weight of the bag, so the shorter bar is usually preferable. However, sometimes the longer bar is needed in order to give enough space for the bag.
Here is the kind of accessory bar that I use:
https://www.sjscycles.co.uk/accessories/genetic-neuron-accessory-bar/For extra space, instead of using the short accessory bar, I cut a 19cm length from the end of one of my old (straight, not drop) handlebars, giving me a 19cm length of 22.2mm straight aluminum bar, and mounted it using two accessory bar mounts. It cuts very nicely on a mitre saw.
There is also an accessory bar that mounts on the top of the steerer, although I have never tried it:
https://www.sjscycles.co.uk/accessories/mounty-space-bar-ii-stem-cap-fitting/- DaveS