The Jetbeam BA20 has a low of 30 lumen and a high of 200+. Like the Fenix, loosen for low, tighten for high, but unlike it, there are only those two modes. It also has a forward clickie for momentary activation.
Here's selfbuilt's review. Looking at the runtime charts, it seems to provide the regulation you like.
Shiningbeam also has their Caveman, 3 mode with 8 lumen low, 130 lumen medium, and 250+ high. Loosen and tighten the head to switch modes. The output levels might not suit you though.
You could also look at the Fenix E21. It's similar to the Jetbeam BA20, low of 40+ lumen, and high of 150 lumen. Loosen head for low, tighten for high, forward clickie. The LD series (LD20+ and LD22 for 2 AA) are still a good choice as well.
