Paul, regardless of what a Quadra head weighs, it's light.
I recently sold my Lumedyne and Norman stuff, and I kind of miss it, especially when asking a VAL to help. In many ways, the weight of the head is more important than the weight of the battery when working in the field. I tried one of the Flashpoint AC/DC lights... the battery was fine, but the head was just too big and heavy. The Calumet Genesis seems to be similar. And I've a strong preference to stay within the PCB system of accessories and triggers, etc.
So there's a big hole between my speedlights and Vagabond setup, and not much under $1500 to fill it with. An AB400 at 2.5 lbs is not bad, and should work okay with the VML... but maybe you could just offer a compact lightweight version for portable use. A 5" reflector would be handy for field use, too.
Anyway, lots of ways it could be tackled, but VML reveals a need for something lighter & more compact at the head; hope you can find time to address it.