I get that…and dedicated higher power bike lights are pricey (more than they should be, imho, always have been). I haven’t tried to keep up with the cheaper brands and such over the years but I wonder if Magicshine has anything decent these days or someone who picked up that ball. Their early ones weren’t so good really, but they were ok and certainly inexpensive. If MTBR still does their annual light roundup, that’s a great resource (even just past years’ reports are worth a look).
Not to niggle but I just weighed my Dinotte with the helmet strap mount and got 135g. My S2+ with a Sony VTC6 is 140g, so another probably +/- 60g for a mount. An ounce (28.35g) doesn’t sound like much but up top it feels like more weight, plus any leverage. Maybe not a deal killer for folks.
There are some flashlights like the Convoy M3 that will put out that much light sustainably for quite a long time, but not so suitable for riding (that one is large and beefy, uses a 26650 cell…plus a small issue that would totally rule it out for night riding). I don’t know of any compact ones that can deliver both qualities. If the riding isn’t so intense it’s not too much hassle to swap out a battery and you can tuck a couple in the pack easily (I’d keep them insulated and protected from any chance of denting in a crash, though).