I had that Cygolite Hi Flux II 150 lumens couple of years back. Trust me nowaday LED lights has came a long way and just about most modern light will be much more brighter than the Hi Flux II. The 150 lumens claim from Cygolite is about right but don't get too high expectation from many of the lumens claim from the newer light based on the product description from the seller. You can expect to get up to 800 to 1000 lumens from a single Cree XML light regardless of the battery type. For a single P7 LED, you might get up to 500 to 600 lumens. This apply regardless of the light being a flashlight or a wired bike light.
For a bar light, it is hard to beat an actual bike light that was design to be mounted on the bar. They typically has better mode selection than most flashlight. The shorter body of a bicycle light is much shorter than a typical flashlight which will have a tendancy to tilt more often than a bar design bicycle light. The runtime from a multiple battery pack from a bar light is also better regulated than a single cell torch light. 26650 battery flashlight does have better runtime and better regulation over a single 18650 cell flashlight but finding a good holder for mounting it to the bar is far and few. If you are worry about theft with a bar light that runs off of a battery pack, you do have the option of taking just the light with you but leave the battery behind. What I did for a while was I place the battery pack inside my pannier on the rack and ran an extension cable to the front bar. The battery is hidden and less likely to be stolen while the light can be unplug and taken with you.
I prefer a torch for helmet light. The footprint of a flashlight has a better profile for helmet mounting than it is using a bar design light. It sits lower and has a more streamline look. There is not wire or battery pack to fuss around. Since most likely you will not be running the helmet on High mode, the battery runtime should be sufficient if you run the helmet flashlight along with a bar light.
Becareful of selecting your light. You should try to research the beam pattern of the light you are planning to buy. Read any review you can find. Just because two light can be using the same LED emitter it does mean they have the same beam pattern. The design of the reflector can easily change a light from flood to a tight spot. Your Cygolite was flood with a semi tight spot but the throw was not very far. That being said, I think any typical flood pattern light with a Cree XML will easily out perform your Hi Flux II.