If you are interested in the modding your flashlight, I think the next thing you should look into is replacing the driver with a LD2. If you are concerned with efficiency, this driver is for you. It is MUCH more efficient in the lower modes…while having near DD performance on high. It’s a pretty easy mod to do…just need a soldering iron and solder.
You may also want to replace the aluminum star with a Noctigon copper star. Reflowing a LED on to Noctigon is a bit more tricky, but you also just buy them pre-mounted .