In general, magnetic anything requires a Hall-effect sensor, and those eat up more power than typical µC hibernation mode. My DV-S9 will drain a fully-charged 26650 in something like 3wks because parasitic drain is 10mA because of its (quite nice) magnetic slideswitch.
Sofirn/Wurkkos diving lights probably have that drain be much lower, but it still drains more’n a regular eswitch.
Point being, I don’t think that’s able to be changed, especially with the “requiring” low-drain for a drawer-light.
At the expense of extra length, there CAN be a mechanical sideswitch, to allow better ergonomics vs a tailswitch. Just like a C/D Maglite, or even my cheepcheepcheep bobofett AA light, they have a deadspace in the tube for a mechanical switch for just off/on.
And for arthritic hands, you don’t need (and don’t want) a skinny body like for an 18650. A 26650 would be fine, as would a pair of Cs or Ds to power it.
An easy-push mech switch would be best, with an oversize button. Especially set off the button with a chromey bezel like the original SC31. At first, that switch looked like a cheap add-on that was just bolted on as an afterthought, but one thing I noticed is that I could always find it, by feel and by sight.
Also, I don’t think a “high” of 150lm would be high enough, as mum had pretty bad fading vision and would have all the lights on in the house that it was like living on the surface of the sun. What’s “bright” to you and me might be woefully inadequate to an old-timer with fading vision. 500lm through a TIR lens (ie, no hotspot+spill) or even aspheric or system like on the S11C, should be an absolute minimum.
And yeah, a lot of old-timers won’t care about multiple levels, which is why those craplights Keep Getting Sold. They’re being sold for a reason, because they’re simple, stooopit, and bright enough (at least on newish alkaleaks), that it just ticks all the boxes. If they’re happy with a craptastic plastic tube with hotwire bulb and simple on/off switch, what makes anyone think they’d want a multiple-brightness light?
One thing that people keep forgetting, over and over and over again, is that…
People don’t want ¼-inch drills, they want ¼-inch holes.
Everyone’s gonna chime in how “useful” it might be for an old-timer to “want” or “need” multiple brightness levels, or strobes (“just in case of emergency”), or this, or that, and then you have a light that’s already overly complicated, if not intimidating. Avoid that trap.