The SP70 host design might be okay but it would require changes in the reflector design (SMO instead of OP), its aperture incl. new centering gaskets and it takes a completely different driver as SP70 uses a 2S (2x 26650 in series) design to drive the 6V XHP70.2 LED. Personally, I recommed to follow up on contactcr's suggestion to develop an extensible host design with a sophisticated buck-boost driver, capable to handle 3p and/or 3s2p or 3s3p (via extension tubes). Thinkin' about extension tubes Sofirn has sucessfully manufactured some prototype extension tubes for Sofirn Q8 (and LT1). The final SBT90.2 light could use following specs:
Redesigned Sofirn SP36 with single SMO reflector and 3p 3V FET driver (with 3x 18650 battery design + n extension tubes to prolong runtime)
Pro: Cost-wise easy to handle, development work would be small, sales prices can be kept as low as possible
Con: Battery format will not make use of the best high drain cells (21700 size), driver efficiency could be better with buck/boost driver
Redesigned Sofirn Q8 with single SMO reflector and efficient buck-boost driver, capable to handle both 3p configuration as well as 3s1p, 3s2p, 3s3p ... by extension tubes)
The Q8 tube needs to be redesigned to use 3x 21700 instead of 4x 18650 to use the benefit of the best 20A+ high drain 21700 batteries (Samsung 30T/40T, Molicel P42A).
Most costs and efforts will be addressed to the driver development but this could pay off in the end with the launch of more high performance premium lights.
Pro: Best USP (unique selling proposition) in competition to Acebeam K30GT and a good way to start a premium line of Sofirn flashlights.
Con: Costs and development efforts would be considerable as well as the increase in its sales price.