If there is a buck/boost circuit Maglite should probably answer "Yes" to the "Power Management" question. So a question that comes to mind with the mini-Maglite is since it has two modes - low & high - how is that done without power management circuitry? I like Maglites but one issue I have is that the company evolved their lights from direct drive Krypton incandescent into LED flashlights and its hard to tell what if anything changed besides the bulb.
I replaced the LED bulbs in my 1989 vintage D-cell Maglites with TerraLUX MiniStar
bulbs. There are 140 lumen bulbs in both 2-3 & 4-6 C/D-cell versions as well as the 50 lumen MiniStar I have in my 2-D Maglite. These bulbs work great imo and the Maglite still focuses like it did with a Krypton bulb.
As to the question of voltage regulation: the MiniStar bulbs are "Electronically regulated for constant light output". So unlike the direct drive Krypton incandescent bulb it replaced, the Terralux bulbs come with their own (voltage?) regulation circuitry inside.
As I recall I got my Terralux bulbs from Batteryjunction.com, but they're also available on Amazon.
Edit: Need to add that if you do a search for "Maglite LED conversion" on Amazon you'll find similar replacement bulbs from Nite Ize, ABN, HQRP et al as well as Terralux. I've used the Terralux bulbs, can't comment on the others.