I guess were both in the same boat. No torch is bright enough, but with all do respect I would leave the TN31 as is. I’ve thought of modding the 7G9 but it really is the longest throwing light I own for now (until something better comes along). Perhaps you should look into the higher end HID’s, that’s a new world my friend of brightness.
It’s already driven at 3.5A and already puts out just over 1000 lumens. You can drive it harder, and it will make it brighter (maybe 200 lumens)but it won’t make a perceivable difference. I don’t know about the heatsinking in this light so I can’t say if the xml will take 5A, but it would sure be fun to try.
Btw, it looks like you’re going to need an SST-90 light if you want more lumens + that kind of throw. You can get over 2000 lumens with a domed SST-90, and still get over 100k lux
I doubt you’d be able to get much more than 1147 OTF lumens out of the XM-L in that light. It’s already a very impressive feat. Making it significantly brighter would involve changing the emitter (perhaps moving to an SST-90 or a multi-emitter setup), the reflector and the driver.