As you said, the intended purpose is very important. When I was planning my thru hike I had several requirements.
I wanted extremely long battery life so I'd have light despite the long hours of darkness I'd experience due to my very early start date.
I wanted it to use AA batteries so that the batteries in all my electronics would be interchangeable or be able to supplement each other.
High brightness was a mere luxury until I spent one long night using all 225 lumens to keep chasing away a persistent cougar.
I ended up with Fenix HP10 that I've been very happy with. Now the new Zebralight looks like it'll provide almost all the same advantages with less weight and bulk.