Try reading the AliExpress customer reviews instead of just looking at the average stars.
The M21C has two reviews, a 1 star review and a 5 star review.
The 1 star review is complaining about not receiving a 21700 cell (that isn’t included).
So, the 1 star review makes absolutely no sense because the flashlight they bought wasn’t supposed to come with a 21700 cell.
I have a bunch of Convoy flashlights, including a bunch of tube lights and 3 different Convoy throwers, and they’re all excellent.
If you do choose a Convoy, get something that is the right size and shape for you with the right emitter.
No matter what you decide to get, don’t just go by the average reviews. 
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The Convoy M21F with 70.3 Hi emitter is an option which might be work checking out. Great form factor and pretty good sustained output with a balanced-floody beam. Smaller than some on this list but still enough meat to outperform something like a D4K at similar temperatures I think.
OP was pretty clear about what he wants when it comes to brightness, flood/throw ratio or even size. Since he was looking at slim Sofirn SC33 (132mm x 32mm) it’s pretty clear those are kind of dimentions we’re talking about. Not 149mm x 48mm/38mm of the Convoy M3. That’s barely smaller than SP36 at 126mm x 50mm and just 10 grams lighter.
Even though he was looking at the Sofirn SC33, he could be interested in a larger flashlight.
And, again, I’m just listing flashlights that fit what the OP has talked about explicitly.
The bottom line is that the OP hasn’t yet said that a 1 x 26650 flashlight would be too large.
The SC33 only makes about 5 cd/lm. 327m (26732 cd) / 5200 lm = 5.14 cd/lm. So it’s a pretty floody beam which is best for short-range use.
The SP36 BLF edition also gets about 5 cd/lm, according to its specs. 350m (30625 cd) / 5600 lm = 5.46 cd/lm.
I happen to like floody EDC lights at 5 cd/lm, like the FW3A and Emisar D4K… but I don’t use them for distance. If I need to see more than ~20 meters or so, I grab a throwier light.
As one example, the FC13 I mentioned earlier has a ~17 cd/lm beam, so it goes farther with less power. This allows a smaller battery to be practical. It’s about 3X as bright at the same power level, or conversely, takes only 1/3rd as much power to reach the same visible intensity.
Personally though, if I need to see farther, I usually go for something smaller and much more throwy – a Noctigon KR1 or Emisar D1, each with 18350 tube and an Osram W1 emitter. It gets about 122 cd/lm (663m or 110000 cd / 900 lm = 122 cd/lm), so it goes a lot farther with even less power. That’s about 25X as intense as my general-purpose light. Because of this, even an 18350 cell is sufficient for my use.
I’m also fond of the D4Sv2, which gets anywhere from ~6 to ~25 cd/lm, depending on which LEDs are chosen… and it can be obtained in a dual channel form which can get both ends of that spectrum in a single light (519A + W2). The 519A flood channel comes in several CCTs and has great color rendering… while the W2 throw channel makes a hotspot about twice as bright as the SP36 with 140m more throw. Just click 3 times to switch between flood and throw. It’s a 26650 light, but more compact than most (105mm long) and it has a very nice-looking beam and comfortable host.
Of course, there are a ton of other options too. Most brands have an EDC style light in the 18650 / 21700 / 26650 size range, with beams anywhere from 1 to 50 cd/lm. Pick a beam type (cd/lm), color temperature, and battery… and there’s probably something reasonably close out there.
Seriously.
“Balanced beam” to me just means a compromise beam. Intense hotspot for looking downstream, but a big bright spill that washes out everything right in front of you. And looking for something right in front of you blinds you with said intense hotspot. So to me it’s not the best of both worlds, but the worst of both worlds.
For probably 99% of what I’d need EDC a light for, it’s close-in work. Grubbling around in a dark closet, looking under a desk, shining on the ground right in front of me so I don’t drop into an open manhole, etc. I want and expect a nice smooth even floody beam. So that’s either a TIR lens or small-reflector setup (eg, triple or quad).
If I need to look at something in the distance, I’ll just use a throwier light. Even a Cat Mini is kinda big, so a GTmicro is nice and compact.
But any throwy light, even with a “balanced” beam, being used for close-in work, is like trying to find something with a laser pointer.
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My recommendation is the light I personally have EDC’d for over a year, belt pouch style. The Sofirn IF25A. Good beam, solid light, plenty of punch when you need it.
If you’re used to carrying the sp36 and want something similar but smaller go for a D4Sv2.
It’s not as small as a d4k but it’ll feel tiny in comparison to the sp36. It’s about half the size, about half the weight, and performance and runtimes are about the same with the right emitters.
If it has to be 21700 then d4k or d1k.
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