I would be interested but I expect at least 2x 21700 5000mah cells for extended run times. I can see this as a perfect gift for contractors if there is a reasonable output mode that can last 8 hours and I definitely buy a bunch for that purpose. I would like to see multi emitter HI CRI emitters like this.
You might be able to source the board and emitters from Clemence at Virence.com
Virence VS35SP36 MCPCB - cost effective (High CRI) General Lighting solution