This light is excellent as it is! It provides a very high output with excellent controls/UI and small form factor. Yes it will go thru the battery quickly if run on high for any time. If you want long run times get an 18650 light, or 2x 18650 or 4x 18650. That is not what this light is for. It is a small pocketable light that can always be carried no matter what you are wearing. By the way, It favorably compares with a custom I have that is over 3 times the cost. It really is a very nice little light (and affordable). The fact it can run on cr123s that are obtainable anywhere (albeit at a lower max output) is a big bonus.
If you feel the need to use 14500s, buy the EA11.
Considering that a lot of people on here complain about “yucky green” tints, I’d guess below the BBL would please them more. So, the 4A or 4D, possibly. Don’t ask me, though, because 4500K is too warm for my taste. 5000K is about the warmest I can stand to use on a regular basis.